In West Virgina at Summit Point Raceway there is a company that does vehicle based training and one of there courses is an off road course. (Its under anti-terrorist driver training). I did an accident avoidance course with them and it had saved me from a nasty wreak on a few occasions. They are a little pricey but they are tons of fun and worth it in my opinion.
Also it is about 70 miles from DC (according to their website)