Yeah Orange County probably would be pretty cheap, but you wouldn't catch me living there, and especially if you're trying to get into acting you likely do want to live closer to where the work is; commuting from Orange County for auditions is probably not something you want to do. You'd probably be better off in the Valley if you want a more suburban setting career-wise, though it's a bit of a trip from there to the ocean, and I don't know anything about surfing etc. so I'm not much help in that department.
There are really so many variables when looking for housing that it's hard to recommend anything specific. It would probably be a good idea to sit down, do the math, and figure out what you're able or willing to pay. Then you can start thinking about location and possibly money-saving questions such as, would you mind having 4 people in a 2 bedroom apartment, or sleeping in the living room of a one-bedroom apartment for lower rent, would you mind if all of your neighbors are illegals, and so on. LA is kind of strange maybe in that you can be in a really nice area with astronomical housing prices, then go down the street five or ten miles and you're in gang territory, and you get the whole gamut of costs right there in a relatively small area.
Excepting Beverly Hills where everything is expensive you can find a pretty wide range of costs in any part of LA, so get a budget, find a general area, and start looking until you find a match. I just used
Craigslist the last time I looked for an apartment, and I've heard there are some strange people on there but it turned out good for me, so your mileage may vary. I personally like West Hollywood a lot (though if you're considering it, keep in mind it's basically the gay hub of LA so you'd want to be very comfortable with that), and if I had to relocate I'd probably look in Santa Monica, Westwood (might get a little expensive though), or Hollywood proper. I just moved out here only last year myself, but if you've got any other questions feel free to send me a PM or whatever. I'd invite you to live in my place but I've already got a roommate.
