David, there are several Chapters in and around San Jose. If you check the chapters page above, you can get the contact information. I know they are all very active and have outings every month with individual members going mining every weekend.

San Jose chapter contact Mike Phillips at svgoldprospectors@yahoo.com. This is from the list published in the Gold Prospectors magazine.

East bay prospectors in Concord is close and I was a member there. They go out at least once a month on a club outing and individuals are always posting for partners to go out with on their website. I learned a lot from them. Joined the GPAA because a Pucky Jurgens who introduced me to the organization. There was a San Jose prospecting club but I do not think they are with GPAA. Central Coast Prospectors in Paso Robles are very active to. And you can just show up on a claim, any GPAA members there will be glad to give you pointers.