Just realized you were asking aobut stores (listed by club associated with store):
Maltose Falcons - home beer wine cheese in Woodland hills. - I go here a lot. very good
http://www.homebeerwinecheese.com/
Pacific Gravity - Culver City HBS - Have been here infrequently since I moved away from the beach.
http://www.brewsupply.com/
Yeast Side Brewers - Eagle Rock HBS - Owned (at least partially) by the guys who own Culver City. All new/fresh ingredients as the place has been open less than a year. Variety is limited, however, especially for hard parts.
http://www.brewsupply.com/
Long Beach Hombrew Club - I don't know about the club, but their home store is StenFillers. This place is great. Lots of ingredients (and they will measure it out for you if you call ahead). Tons of keg and serving parts too.
http://www.steinfillers.com/