What Did Jesus Look Like And Does it Matter?
Because Jesus as a man is the focus of more art than any other figure in the history of the world, most Westerners are pretty confident that they know what Jesus looked like.
The churches most of them attend have paintings or stained glass windows that depict Him as a tall, rather good looking, fair-skinned man with fine features and a serene expression. He is usually portrayed with long (usually brown) hair, a beard, and even (on occasion) light eyes. Also common are a full length (often white) robe with a red or blue outer mantle. Family Bibles, calendars, books etc. also present this Caucasian Jesus as do the movies and television, including History Channel's 2013 hit series The Bible.
Unfortunately, none of them have given the matter a modicum of thought.
Does it matter?
Yes it does. This largely because highly inaccurate portrayals have done their part in promoting...
Racism and Antisemitism
While all Christians are (or should be) aware of the fact that Christ as Lord transcends skin and race, depicting Christ as white has led to a disconnect in the minds of many Christians. All too often, the underlying image of God choosing to come to earth as a white man is very likely to have played a big part in the racism displayed by many who claim to be followers of Christ.
However, other than reminding them that God Himself came to earth as a Jew - a member of His chosen race, I have absolutely no idea what to say to those who claim to be Christian but are anti-Semitic. It is one of the most despicable to say nothing of bizarre contradictions I have ever come across.
Anyway, to return to the original question - only the people who had actually met or seen Jesus would have known exactly what He looked like However, Isaiah (53:2) did say that the Messiah would have no stately form or majesty and His appearance would not particularly attract people to him (so much for all those good looking actors who have played Jesus).
Anyway, although the Gospels do not enlighten us at all, much evidence can be gathered from archaeology, ancient art, small clues in the Bible, and plain common sense. Which means we have a very good idea of the general physical characteristics of a first century Jewish male - how he wore his hair and dressed.
And it is very safe to say that any of the disciples presented with a modern depiction of the Savior would wonder who that was.
The last phase of construction of the Dura-Europos house church in Syria was dated by an Aramaic inscription to 244 AD, making it one of the oldest synagogues in the world. What is amazing is that upon excavation the structure itself was not only pretty much intact, but so were the extensive wall-paintings now displayed in the National Museum of Damascus.
The various Old Testament figures such as Moses, David, Samuel, Moses etc. were all depicted with short, often curly hair. A painting of Jesus healing the paralytic man (Mark 2:1-12) on a wall of the baptismal chamber portrays Him as not very tall, olive skinned with short curly hair. A closer look also shows that the figure has some hair on His face, which would have been normal for Jewish men. SEE
The painting can be considered realistic considering that archaeological remains, historical texts, statues etc. showed that people in Judea and Egypt had brown eyes, black hair and olive-brown skin. In fact, how many really tall, light haired, light skinned, ascetic looking middle eastern men have you ever met or even seen?
There was interaction between Judea and people from Europe (who could have lighter skin) as well as Sudan and Ethiopia (who could have darker skin). But because Jews in Judea and Egypt tended to marry among themselves at the time, Jesus' skin, eyes and hair probably looked like those of the majority of the people in Judea and Egypt, 
In other words, modern portrayals of Jesus have arisen not from any realistic ideas of what a 1st century middle eastern man looked like but from...
Byzantine Theological Portrayals
During the 4th Century Byzantine era representations of Jesus were meant to be symbolic, not literal. For example, a mosaic in the 4th century Santa Pudenziana church in Rome shows Christ enthroned among the Apostles. He bears more resemblance to the statue of Zeus in Olympia, Greece than anything else.
Zeus was considered to be king of the gods of Mount Olympus therefore in all likelihood the depiction of Jesus (in a gold toga no less) was intended to show Him as an enthroned emperor. The halo above Jesus' head was originally a feature of the sun god (Apollo). Note the Roman Emperor Augustus had a statue of himself made in the same style minus the long hair and beard.
In other words, the images did not intend to particularly show Jesus as a man, but to make the point that He was King. Unfortunately, these images gradually became standard portrayals of Jesus - the man.
Hair and Beards
Numerous statues etc. testify to the fact that men in the Roman world were largely clean shaven and short-haired. See Wikipedia Article Emperor Hadrian might have been the first emperor to wear a beard. However, beards were very important to Jewish men, so much so that when some of them lost theirs they were so humiliated that they had to wait for it to regrow before they returned to Jerusalem.
So Hanun took David's servants and shaved off half of their beards, and cut off their garments in the middle as far as their hips, and sent them away. When they told it to David, he sent to meet them, for the men were greatly humiliated. And the king said, "Stay at Jericho until your beards grow, and then return." (2 Samuel 10:4-5 NASB)
Additionally, although it might be metaphoric, a prophecy in Isaiah particularly mentions a beard
"I gave My back to those who strike Me, and My cheeks to those who pluck out the beard; I did not cover My face from humiliation and spitting. (Isaiah 50:6 NASB)
And Jewish males did not have long hair. As Paul wrote to the Corinthians
Does not even nature itself teach you that if a man has long hair, it is a dishonor to him, (1 Corinthians 11:14 NASB)
The only exception would have been the Nazarites who were consecrated to the service of God usually for a limited period of time. The vow of a Nazarite involved three things, (1) Abstinence from wine and strong drink (In fact they avoided eating anything that was made from the grape vine) (2) They refrained from cutting their hair and (3) avoided all contact with the dead. See Numbers 6. At the end of the period, they cut their hair and made an offering to the Lord at a special ceremony at the temple in Jerusalem. Note Acts 18:18 indicates that Paul once took the vows of a Nazarite.
"Paul, having remained many days longer, took leave of the brethren and put out to sea for Syria, and with him were Priscilla and Aquila. In Cenchrea he had his hair cut, for he was keeping a vow".
Scripture tells of only three men who were Nazarites for life - Samson, Samuel, and John the Baptist (Judges 13:4-5; 1 Samuel 1:11, and Luke 1:15) Jesus was certainly not a Nazarite. He drank wine (Matthew 11:19) and raised a little girl from the dead by taking her hand (Matthew 9:23-25). Thus it is safe to say that the Savior had short hair with a short beard.
We are attuned to pictures of Jesus wearing immaculate long robes which is extremely unlikely. There were three primary garments worn by most Jews - the tunic, a belt of sorts, and the outer shawl worn like a mantle. As Matthew 5:40 says
"If anyone wants to sue you and take your shirt (Gr. chiton), let him have your coat (Gr. himation) also.
Although in the verse above, the Greek chiton has been rendered 'shirt' (seriously?) it is usually translated as tunic that was belted and fell halfway between the knees and ankles. As said by Encyclopædia Britannica,
For men the chiton was usually knee-length and seamed up one or both sides. An ankle-length version was worn by women and for more formal wear by men. 
A mantle or shawl which was a large rectangle of fabric(similar to the Greek himation) was worn over the tunic perhaps draped in different ways.
In fact, Jesus pointed out that the scribes liked to dress up in long robes to show off their status and impress people with their fine attire.
"Beware of the scribes who like to walk around in long robes, and like respectful greetings in the market places, and chief seats in the synagogues and places of honor at banquets, who devour widows' houses, and for appearance's sake offer long prayers; these will receive greater condemnation." (Mark 12:38-40 NASB)
Thus pictures of Jesus in long robes are entirely inaccurate.
In Numbers 15:37 the Lord instructed all Jews to put tassels on the corners of their garments with a blue cord or thread in the corner tassels.
The Lord also spoke to Moses, saying, "Speak to the sons of Israel, and tell them that they shall make for themselves tassels on the corners of their garments throughout their generations, and that they shall put on the tassel of each corner a cord of blue. "It shall be a tassel for you to look at and remember all the commandments of the Lord, so as to do them and not follow after your own heart and your own eyes, after which you played the harlot, so that you may remember to do all My commandments and be holy to your God. "I am the Lord your God who brought you out from the land of Egypt to be your God; I am the Lord your God." (Numbers 15:37-41 NASB)
The tassels were to be a visual reminder of who the wearer was and the commandments he was pledged to obey. I can see how that worked. Many years ago I had a small credit card sized plastic card I carried in my purse. It had a tiny wooden cross affixed to it and although I do not remember all it said, the opening line was "I carry this cross in my pocket as a simple reminder to me of the fact that I am a Christian no matter where I may be".
And Jesus certainly had tassels on the edge of His cloak
Wherever He entered villages, or cities, or countryside, they were laying the sick in the market places, and imploring Him that they might just touch the fringe of His cloak; and as many as touched it were being cured. (Mark 6:56 NASB)
And a woman who had been suffering from a hemorrhage for twelve years, came up behind Him and touched the fringe of His cloak; (Matthew 9:20 NASB)
However, Jesus condemned the hypocritical Pharisees for "enlarging their fringes". They purposely made their tassels as long and as conspicuous as possible so that they would be seen as pious and holy. (Matthew 23:3)
The Second Commandment
Apart from the fact that portraying Jesus as a white Caucasian male insidiously lends itself to racism, there is another equally important question - Is any picture of Christ a violation of the second commandment that forbids the idolatry of bowing down or worshipping an image or likeness of anything in or below heaven ?
'You shall have no other gods before Me. (8) 'You shall not make for yourself an idol, or any likeness of what is in heaven above or on the earth beneath or in the water under the earth. (9) 'You shall not worship them or serve them; for I, the LORD your God, am a jealous God, visiting the iniquity of the fathers on the children, and on the third and the fourth generations of those who hate Me, (10) but showing lovingkindness to thousands, to those who love Me and keep My commandments. (Deuteronomy 5:7-10 NASB)
(For an explanation of verses 9 and 10 see Generational Curses
On the other hand, a picture of Jesus can simply be reminder of Christ similar to the tassels with blue thread Jewish men were instructed to affix to their cloaks.
However, all too often pictures of Jesus or even a crucifix become objects of worship which is definitely a violation of the Second Commandment. Prayer, worship or adoration is not to be offered to an inanimate object. To use a likeness of Christ as an aid to worship is forbidden by the second commandment as much in Christ's case as in that of the Father and Spirit.
Footnote - Breeches
(net necessarily related to the topic in hand, but interesting all the same)
"And you shall make the altar of acacia wood, five cubits long and five cubits wide; the altar shall be square, and its height shall be three cubits. (Exodus 27:1 NASB)
The cubit is the distance from the elbow to the fingertips so probably varied according to who was doing the measuring. However, it is generally believed to be between 17.5 and 20 inches. Therefore 3 cubits would be about 4.5 foot. (However, 2 Chronicles 4:1 says Solomon's temple was much taller at ten cubits or 15 feet off the ground). Additionally, the description of Ezekiel Temple clearly states that it had steps
"The ledge shall be fourteen cubits long by fourteen wide in its four sides, the border around it shall be half a cubit and its base shall be a cubit round about; and its steps shall face the east." (43:17)
Many people interpret Exodus 20:26 to mean that the priests were forbidden to ascend the altar by steps and that in fact there were no steps leading to the altar. However, this command was addressed not only to the priests but to the "Sons of Israel". See verse 22.
'And you shall not go up by steps to My altar, so that your nakedness will not be exposed on it.' (Exodus 20:26 NASB)
Quite obviously the short tunics worn by men could indecently expose anyone going up the steps, which must be why the priests were later on commanded to wear linen breeches (pants) that equated to long under pants (from the loins to thighs).
"You shall make for them linen breeches to cover their bare flesh; they shall reach from the loins even to the thighs. "They shall be on Aaron and on his sons when they enter the tent of meeting, or when they approach the altar to minister in the holy place, so that they do not incur guilt and die. It shall be a statute forever to him and to his descendants after him. (Exodus 28:42-43 NASB)
"Aaron shall enter the holy place with this: with a bull for a sin offering and a ram for a burnt offering. "He shall put on the holy linen tunic, and the linen undergarments shall be next to his body, and he shall be girded with the linen sash and attired with the linen turban (these are holy garments). Then he shall bathe his body in water and put them on. (Leviticus 16:3-4 NASB)
Ezekiel 44:15 -19 makes it very clear that before the priests exited the inner sanctuary they left these garments behind and donned their regular clothes.
 Owen Jarus. What Did Jesus Really Look Like? New Study Redraws Holy Image.