As was said, the local chapters are a wealth of information, and the members are usually more than willing to help out the new folks. There are no dues to be a member of a chapter, but eventually you might end up joing GPAA once you get involved. You might also check with your local Chamber of Commerce and see if they know of a local club or group. If you have a mining store or even a BLM/USFS office in the area, check with the mineral person there, they would usually know of any groups as well.
Welcome and good luck. If you are in our area, you are always welcome at our meetings. (centralWillamette Valley Oregon)