I belive at one time you could camp out at a few beaches can be no more than 10 - 15 dollars a day. I dont know of any hotels anything to the beach has to be $$$$ But if money is a concern camping out could be a good alternative
i went to cali this summer and stayed at a best western in oceanside in sandiego. if you stay there you can travel up and down the pacific coast highway and find surf where ever you please. thats if your going to san diego if your going to LA im sure there are a bunch of places you could easily find with a cheap rate