Well, you need to decide which saber you want to make.:confused
Is it one from any of the films? Is it to be a custom? Do you want real, authentic parts? Do you want it to be machined?
Lots of variables to what you're asking, so I'd suggest, decide which one you'd like to make, then do a search for that saber in the search bar at the top. Lots of saber conversations going on right now. If you're not sure of the name of a particular saber, drop me a PM & I'll see if I can steer you in the right direction.:thumbsup
As to building, most lightsabers are either made from a chromed tube or they are machined on a lathe from (mostly) solid aluminium stock.
Many builders start out with chromed brass sink tubes from the hardware store. The downside with them is that the brass shows where you have cut it.
I like aluminium tubes. Aluminium is quite easy to work with and it is what many of the lightsabers in the movies were made of.
Tools: Sink tubes are best cut with a tube cutter (if you can find one that can cut 1 ½"). Otherwise hacksaw with miter box, Dremel, files, and sandpaper for finishing.