wrxstiPSYCHERN - Before coming out to CA, I would suggest having a job lined up already. As the state is significantly oversupplied with experienced RNs and new grads. Making RN jobs few and far between.
Also, there is a statewide hiring freeze at the eight state mental hospitals which has been discussed exhaustively on this forum. The CA prison healthcare system might be hiring soon, as they under a federal court order to spend an additional $8 billion to upgrade prison healthcare. But the governor/legislature has been fight this in the courts for the last two years, so it may not happen soon.
One of the posters above mentioned the George Pavilllion in Concord. There is a John George Psych Pavillion in San Leandro that is Alameda County's PHF (Psych Health Facility). I had a clinical rotation there, and the clientele were mostly inmates from the local jails, and transients/homeless. It was roughhhhhhhh. I was constantly being pulled into dangerous situations, and I never felt safe there (and I'm a pretty big guy). There is a Private Psych hospital in Fremont named "Fremont Hospital" which occasionally posts jobs. And John Muir Hospital in Walnut Creek/Concord has a Behavioral Health Unit which I've heard good things about.
If you are okay with working in a prison, then San Quentin State Prison is almost always looking for nurses. They are on the Bay, just a short ferry ride from Vallejo, and they have pretty attractive compensation packages (w/bonuses, pensions, etc). The hiring process takes about six months. I have a friend working there. and she likes it.
Good Luck, R