Steve,
The Blackhawk meet was organized here in the Zone 7 Forum. So, if you just check in here you will know what's what.
The Saturday breakfast at Marie Callender's in Walnut Creek is sponsored by the Diablo Region of the Porsche Club of America. They, along with the Golden Gate Region, have a web site with an events calendar. So check out their web sites.
I'd say between joining
PCA and one of it's local clubs and hanging out at Cayman Club, you will find everything you need to know.
BTW-the Zone 7 Forum has been quiet through the winter. Hopefully things will pick up in Spring and Summer.