San Diego is AWESOME. I've never moved cross country, but one of my friends moved to San Fran. from MIchigan and I helped her plan everything. If you need to find a place anywhere in California craigslist is a good way to do that. I'm sure the UCSD website also has some sort of link to off campus housing help.
Depending on how much stuff you are bringing with you, the cheapest way to do it would be to get a drive it yourself truck and get a (very nice, generous) friend to driv eit for you, and follow in your car, or if you have lots of stuff and money, hire movers, ship your car, and fly out to CA which would probably be easier on you, however probably much more expensive.
Also be aware CA has ALOT stricter emissions standards than some other states, so you may have to do some stuff to your car to get it registered here. This site may give you some hints about doing that.
CA DMV website Also be prepared for your car insurance to go up as well. That is all I can think of besides to say I think San Diego is an AWESOME city and that I spent two weeks at UCSD with a friend who went there and you should have an awesome time.
To meet people don't forget about TPA Alum chapters and if there isn't a TPA one, try an alumnae panhellenic group, I'm sure there's one in the SD area.