tracks in So Cal?

[86turbo]

I'd like to get some experience with my car on the racetrack, but I'm totally ignorant to this experience. First off, does anyone know of any good road racing tracks in southern California, preferrably around the Riverside area? (not just an oval track, I want turns). Keep in mind I'm a beginner, I consider myself a decent driver (don't we all) but would it be wise to invest in a performance driving class of some kind? Which would you recommend? Or could I just "take it easy" around the track the first few times til I'm familiar with it. How should I prepare my car, what should I expect? How much should I expect to pay to use a racetrack? Thanks, and sorry for my ignorance... at the very least I suppose I'm bringing some conversation to this place!
Dan