Well I don't have any of the material on me, but off the top of my head the weapons from FS:FPS (set during the V-T war) included:
Terran
Ammunition Based (Caseless Collapsed Shell Uranium for the bullets, I forgot what was the caliber but Plasma had it written down, all of the ammunition was universal and could be used in every gun)
Automatic Pistol (Inaccurate automatic primary fire, accurate semi automatic alternate fire)
Heavy Assault Rifle (the one seen in the Hallfight Cutscene. Fully automatic, one idea being bounced around was a "replay" feature where secondary fires a TAG and the bullets redirect to the TAG bullet, sort of like the weapon in The 5th Element)
Energy Based (Uses Deuterium fuel cells to power the reactor)
GTW-X Banshee Rifle (A very large, cumbersome weapon, when fired it creates a high pitched shriek which can deafen civilians and those not using hearing protection, it effectively acts like a rocket launcher in most games)
Vasudan- Basically weapons designed for multiple use including melee as Vasudans are naturally strong and powered armor strengthens them even more so. Mainly designed for long range and short range combat only, with a definately lack of medium range weapons.
Ammunition Based
Sniper Staff (A very accurate rifle, as well as a sturdy bludgeoning melee weapon)
Energy Based
"Punch Daggers" (Similar to Katars, these daggers can be used for a melee attack or can be used for a raw short range energy discharge)
That's pretty much all I can remember at the moment. I know that quite a few more weapons were worked out.