Looking for beach camping recommendations in SoCal...

You have to book San Elijo and So. Carlsbad on the 1st of the month 6 months before you want to go at 8:00am (going to Carlsbad next month, 6 families each had 2 computers trying to get sites, not all of us got one). Both of those are better than all the other state beaches mentioned, Emma Woods is cool though.

You could try a couple private ones on the bay by sea world.