We stayed several days in this spot in Puerto Escondido. We liked the place a lot, very simple, super close to the beach, and cheap. I actually liked it so much that I offered Victor, the owner, to make a website for him. And here it is: http://campingmarinero.wordpress.com.
There’s four or five spaces for tents or small campers/pickups.
Definitely a way better option to camp than the other two (very dumpy) campgrounds nearby.
steph