You will need to cruise the individual sites to get the star party info.  The two easiest are SAN JOSE ASTRONOMICAL ASSOCIATION SAN JOSE which has public viewings twice a month on Fridays and Foothill Observatory, which is every Friday.  Currently Foothill is closed for upgrades, but should open again soon.
(If a link is bad, let me know)

FOOTHILL OBSERVATORY
http://www.foothill.fhda.edu/ast/fhobs.htm

EASTBAY ASTRONOMICAL SOCIETY, INC. OAKLAND 
http://www.eastbayastro.org
 

HALLS VALLEY ASTRONOMICAL GROUP SAN JOSE
http://www.snap-design.com/HVAG/
 

PENINSULA ASTRONOMICAL SOCIETY MOUNTAIN VIEW
http://www.foothill.fhda.edu/ast/pas.htm
 

SAN FRANCISCO SIDEWALK ASTRONOMERS SAN FRANCISCO
http://www.sfsidewalkastronomers.org/

SAN FRANCISCO AMATEUR ASTRONOMERS DALY CITY
http://www.sfaa-astronomy.org/sfaa/
 

SAN JOSE ASTRONOMICAL ASSOCIATION SAN JOSE
http://www.sjaa.net/
 

SAN MATEO ASTRONOMICAL SOCIETY SAN MATEO
http://home.covad.net/~alcoat/smcas/smcas.htm
 

SANTA CRUZ ASTRONOMY CLUB SANTA CRUZ
http://astro.santa-cruz.ca.us/
 

SONOMA COUNTY ASTRONOMICAL SOCIETY SANTA ROSA
http://www.sonomaskies.org/
 

THE ASTRONOMY CONNECTION BAY AREA
http://www.observers.org/