I live in West Oakland, California. I sail a mostly 1986 Hobie 18 that I have had for about a year and a half. Prior to buying the Hobie I assembled a fleet of 4 Hobie 16's at Lake Merrit in Downtown Oakland, where I worked as a volunteer. I started sailing Cats back in the early 80's on my pal's Prindle 16 out of Marina Del Rey and a few So. Cal lakes. He bought a Prindle 18.2 a few years ago and I got back into it in a big way.
I sailed about 15 days this summer, mostly on lakes in Northern Califronia whithin about 4 hours of the Bay Area. My Fiance' and I completed our first regatta (on my own boat) this July, and we almost won the whole thing!
I wish I could find others interested in these things in the Bay Area, but it is a pretty dead scene.
We plan to sailat least as much next summer.