Hey everybody. You may or may not know that blizzard has placed three weapons into the game that are very similar to appearance as a lightsaber, from the ever popular Star Wars universe. One of these, Teebu's Blazing Longsword - Item - World of Warcraft , is an extremely rare world drop, so I will not be focusing on it. The other two are quite simple to get, and even better if you are a class able to dual wield swords.
1) Perhaps the easiest to obtain if you are a level 80 character, though a little more reliant on RNG, is Spellfire Longsword - Item - World of Warcraft , Which drops from Mennu the Betrayer in Slave Pens (normal). It is a main hand weapon, however, so you will have to get this next item if you want to dual wield them.
2) This weapon, Argent Avenger - Item - World of Warcraft , is gained through a slightly tedious quest chain, involving having to go to Stratholme on a couple of occasions.
First off, you will want to get The Archivist - Quest - World of Warcraft from Duke Nicholas Zverenhoff at Light's Hope Chapel.
Now, blast your way through Strat - Living, and kill Archivist Galford, being sure to burn the study down.
This next part is great for saving time. Don't continue with the instance. In the very next room is another boss, but do not kill him. Instead, go and turn in that quest, and quickly make your way back to that boss. This will allow you to skip a bit of trash.
This time, just rush in, insta-gib boss, and he will drop a head that starts a quest, Head of Balnazzar - Item - World of Warcraft .
Take it back to Light's Hope, turn in, and accept the next quest, which requires you to go and kill Baron on the Undead side of Strat. Feel free to make it a mount run while you're at it, you may get lucky.
Kill baron, return to Light's Hope, turn in, and then accept the next quest, which just requires you to speak to Lord Maxwell Tyrosus inside the Chapel.
He will give you a quest where all you have to do is interact with the chest next to him, and you've got your second lightsaber.
The best part about this chain, for those who care about achievements or whatnot, is that it not only counts towards Loremaster, but it also nets you 4500+ rep with the Argent Dawn.
What is great about these lightsabers is that you can enchant them, and the enchants do stack with the lightsaber glow. I.E Demonslaying to get a purple glow, or Mongoose for a straight up bad ass look.
Hope this short guide helps!
[EDIT]
Here's what they look like guys!
Enjoy!