Lots a sage advice in the posts above. I would add that since you are in CA, keep your options to cars that are older than 1973, that way you are exempt from smog testing and you are not limited in your options. Since you are "bucks down" (vintage phrase) you might want to look for something that is not the In thing. You can find a 55 Buick or Olds for a lot less than a 55 Chevy. The downside is the parts are less available, but they are out there. Another thing to think about is a bigger car is cool if you want to take the whole gang along, but they are also more expensive to operate. One of my high school buds had a 48 Chevy 4 door that we could put about a dozen people in. In addition to going to cruise nights, watch the local paper keep you eye out for cars in peoples side yards or behind repair garages. Sometimes people will be happy to have you get rid of something they have had sitting.

By the way, 50s and 60s Studebakers are still around and sometimes can be had pretty cheap. Parts are suprisingly available for them too.

Good luck with your search and keep us posted.