For all Los Angeles is a center for MMA in the US, there don't seem to be many places offering classes that are MMA- usually it's either BJJ/subgrappling, kickboxing, thai boxing, but few places seem to have 'pure' MMA classes where people can put it all together.
If you know of a place that does this, please add it to this thread.
Here's what I know so far
RAW gym- team practice- El Segundo http://www.r1gym.com/
Centerline Gym- Bellflower (SBGi affiliate)
Hayastan (occasional Sundays)-Hollywood
Inosanto Acadamy- Marina del Ray
Beverly Hills Jiu Jitsu- Beverly Hills
There was a school in West LA looking for heavyweights posting a while ago, but I haven't been able to find them.