The best weapons ive seen are:
Combat Rifle
142 dmg, no elemental
80% xtra dmg
60% faster reload

Sniper
489 dmg, no elemental
120% xtra dmg
70% xtra crit.

Revolver
235 dmg, no elemental
4got xtra stuff

i'll post the names next time i log in on LIVE

162 damage Assult Rifle. I havent played in I while so I forgot the name.

2641 DMG Revolver. It's white, no Element, 59 Level Requirement, 150% Critical, 1.2% Zoom, and bayonet on the end(200% Melee Damage)

Got it when I beat Crawmerax.

1474 DMG Sniper. It's gold, no Element, 60 Level Requirement, 230% Critical, 1.0% Zoom.

Also when I beat Crawmerax.

I don't pay attention to names.

Then of course, the modded Repeater pistol my friend made for me. I don't use it(Not a noob) but I keep it for memories, he quit XBox.

72546958 x5(shoots 5 bullets) DAM, it's Forest Camo, 9001% Chance to make the enemy explode, 2 Level Requirement, 1337% Critical, no zoom.