Check out the SETRA website, they have the new Enduro and Hare Scramble schedule up. There are plenty of races in the NE GA and SC area. The Long Cane enduro is next weekend, it is near Abbeville, SC. Also, you can can ride at Manchester in SC, it is an OHV/ORV that has track and trails Aonia Pass is in Wasshington GA, they have a decent MX track and some great trails. The trails are only used for races and special events. They have the "Santa Clause" Hare Scramble in December.
I live in Columbia, SC and work in Augusta, GA. There is a fairly tame MX track near Edgefield, SC. They have held HS there before, but I don't know if the new guy who bought the track also bought the land where they had the trails.
The SCORE (South Carolina Off-Road Enthusiasts) website lists some riding areas. I don't remember the url, but you can get there from www.tntmotorsportsinc.com.
How far would you go to ride? TNT is about 110 miles, so is Manchester. Aonia (track only) is about 45.
I've been riding in Atlanta and actually started leaving my bike up there. I have some friends that have property about an hour from here but it's just farm and very dull. I'm looking for some great trails, I'm willing to drive for something worth experiencing.