I've gone out herping several times with some friends, and so far I have personally seen the following:

Black-Necked Garter Snake
Checkered Garter Snake
Sonoran Lyresnake
Spotted Leafnosed Snake
Desert Nightsnake
Variable Sandsnake
Long-Nosed Snake
Threadsnake (also known as a Western Blind Snake)
Western Diamondback Rattlesnake
Mojave Rattlesnake
Tiger Rattlesnake
Sidewinder.

And, of course, I do have pictures of all of these...except maybe the Mojave (not sure).