The Shelby Club has their big annual event coming up at Sears Point (I refuse to call it by the other name!). However, last week was the cutoff for registering (you might contact them and see if you can squeak in). Their web site is
http://www.norcal-saac.org/.
Shaun, Billgear and I are already signed up and I think that Mytoys is as well. Several other VMFers will probably be there as well. Even if you can't get a spot for the open track, it's still a great idea to make the trip to Sears Point: you'll see what it's all about and should be able to get your car onto the track for a parade lap (no faster than 65, but if you've never been on a track before, you get the adrenaline rush out of the way!).
If you can't make that, then I highly recommend the Fall Classic (also with the Shelby club) at Thunderhill in October. It's a GREAT track, with wide open spaces for runoff (not that you'd need it, but it's nice to see that open field as opposed to a wall!).
Send me a PM if you have questions: we love to talk about Open Track! You might also check out the Green Flag Driving Association and NASA websites as they also host Open Track events.
Hope to see you there!