My old friend from Houston, John Zeigler, teaches bass, although his primary emphasis is his monster guitar playing. But he could certainly open your eyes, as he is a great player, and if he was not to your liking, he could turn you onto some of the best teachers in the LA area, no doubt.
Don't let the fact that he is a six stringer mislead you. The man can teach the bass, and was reknown in Houston as the teacher of both 4 and 6 string guitars.
Here's his site:
http://www.johnzguitar.com/
He has a weekly jam on mondays at the Baked Potato. Tell him Greg, a formerly from Houston drummer who occasionally played with him in his monster lineup "The Slashers" back in the late 80's said hello. He hangs and plays with some heavy cats, again, if he is not to your liking, he will know the monster teachers.
I'm actually going to be in LA in two weeks. Where are some good places in and around the west side to hear some great acts, local or otherwise. I'm big into the blues, where can I get some blues action?