There's also a nice room in Santa Cruz called Surf City Billiards:
http://www.surfcitybilliards.com/
Not much in the way of action when I was there but the GC4's are first rate and the food is decent.
In Capitola there is
Fast Eddie's. It's a little dumpier than Surf City but you will probably find more action there.
Both are up the coast about 1/2 an hour or so.
And of course, about 90 minutes away or so is the
California Billiard Club in Mountain View. A little far to go just to knock balls around but worth the drive for a tournament or if you are planning to stay the whole day/evening.