We just did this route as part of our big trip. Took I-5 to LA, then over to Santa Monica, up the coast from there. Camped at Carpinteria (TINY campsites, at least where we were, but terrific beach/town). Continued up the coast for a bit, then towards Solvang and over to Monterey, camped at Marina Dunes. Next headed up through Paolo Alto (left the coast somewhat accidetally), toured San Fran, and across the golden gate bridge. Be SURE to be in the outer lanes when crossing the bridge. The left lane puts you through the old toll booths which are NOT RV friendly. We then stayed on 101 through Sonoma etc..and camped at Ancient Redwoods RV, very nice setting, but none of the ones I mentioned may be your cup of tea if you like boondocking.
We did try to tour hearst castle, but hadn't prebooked and were out of luck. Friends like to camp at Jebediah Smith National Park near crescent city, so would be worth checking out. Terrific Beach camping in Oregon, if you decide to travel a bit further north. Have fun!
