quite a few
Don't forget Bear Creek's new indoor field in Milpitas and Sunol Paintball (outdoor) and another indoor field in Hayward called Operation Paintball.
http://www.bearcreekmilpitas.com/ (FPO and NO CO2 tanks allowed) http://sunolpaintball.com/ (BYOP, has refills for co2)
http://www.operationpaintball.net/ (FPO, NO CO2 tanks allowed)