There is a poker run held in Perry GA every three months, at the site of the Hi Point National Hare Scramble. It's the same track they run the National race on, usually about a 12-14 mile loop, and the event is very well organized. Send me an email with your addy, and I'll send you the date for the next one when I know.
There is also a large area in Albany GA, mostly large sand dunes, that is an excellent place to ride. I grew up riding there, the place is enormous, with 60-70 ft high dunes, and tons of trails. It is located on hwy 82, between Albany and Sylvester, just east of the Flint River. You can see the dunes from the hwy, you can't miss it.