I can definitely help there. How about one of the best singletrack trail system's in the country? Yes we have that here. In fact, the International Mountain-biking Association (IMBA) is having their world-wide convention in good-old Augusta GA next May! The main trail system is called FATS -- there about 40 miles of trails in that system alone. The trails are actually just right across the border in South Carolina about 10-15 minutes from Augusta. Here is a map of the trail system that one of my mountain-biking friends put together:
http://maps.google.com/maps/ms?hl=en&ie=UTF8&msa=0&msid=112493191138240861154.0004351308c52f1b7228a&z=10

Here is also a good site for the local SORBA chapter: http://www.sorbacsra.org/

Its a big no-no to ride FATS when its wet. This site will let you know if the trail is open or closed. Generally after a heavy rain, the trail will close for 24 hours, sometimes 48.

the best trails for a windsurfer might just be in the water...if you SUP!!!