Come on up to vir's charity lap day in the fall. Great way to see what tracking is like, but safe enough and cheap enough not to break the bank if you hate it.
Another great option is a "Hyperdrive" at any NASA Mid Atlantic event. That's one HPDE1 equivalent session with an instructor, usually for $50, and membership is not required. http://www.nasaracing.net/?page_id=85
(The VIR thing mentioned above is just touring laps behind a pace car iirc...)