Ah! Dave, thanks for asking the question and thanks for the clarification, Andy.
An easy way to get started in autocross is to simply attend one! There is (or at least was, when I lived in Lancaster, PA) a very active autocross community thriving right around you. The Farm Show complex in Harrisburg is still one of the best autocross sites in the country. They also used to have autocrosses at a couple places near Philly - near Valley Forge and across the river in Camden. I imagine they don't use Fort Dix in NJ any more post 9-11, but that was another good one.
Check out this link and just email one or two people in the SCCA regions near you or do some google research - I bet they have websites with autocross schedules:
http://www.scca.com/Inside/index.asp?reference=nediv
All you need to do for your first autocross is show up with a technical sound and safe car with everything cleaned out of the interior. Most places will even have loaner helmets. That's IT! It is usually $30-40 bucks entry fee for the day.
Best of luck!
Dean