You might try Laguna Seca. The campground is very nice, just don't go on motogp weekend
Even if there's a car event there's usually space available with great views; the track shuts down by about 4:30 usually. And there's a shooting range within the park.
Other good ones not mentioned:
Lime Kiln State Park: either shaded or beachfront camping below Big Sur. Plaskett is also nice, but I like Lime Kiln better.
Salt Point: best campground is Gerstler Cove; busy in summer but nicer in winter. Stillwater Cove, a county park nearby, is also nice but not on the water. Some nice backroads to cruise. Bodega Dunes isn't quite as nice, but often available when the others aren't.
Hollister Hills SVRA: stay somewhere at the upper ranch, or even at the motorcycle part. Noisy and frenetic, but you can see some really cool vehicles and driving. And cheap.
If you just want a nice camping weekend, try our East Bay Parks campgrounds: Del Valle (right on a reservoir, plus nice mountain biking and hiking) or Chabot (again, nice hiking and biking, and a nice shooting range on site which you may have seen on Mythbusters).
Some other state parks, if they're still open for camping: Mount Diablo (great views, and the whole mountain is closed at night so it's real quiet) or Big Basin (Berry Falls is a great hike in winter). And near the limit of your range is Morro Bay and/or Montana del Oro (the former has showers and whatnot, the latter is more primitive but prettier, especially with flowers in the spring). There is also a NF campground off 41 nearby but haven't tried it.
For something different try Brannan Island in the Delta. Not the nicest campground, but exploring the Delta is something fun to do, although having a boat is a big plus. Or if you like windsurfing.
That should get ya started.