San Francisco bay area is a big area composed of San Francisco, San Jose, and a bunch of places inbetween.
Check out OneCypher's updated list of classes and sessions.
Also the bboy fb group keeps a list of bboy sessions.
There may be sessions, clubs, and parties that don't show up above or on http://www.dancedeets.com. Check out One Cypher for some good information, particularly "Event Calendar" and "Classes/Sessions" on the right-hand side too.
Also these FB groups may be of interest: