You have the perfect destination in mind(Waynesboro). Your start point is Amicalola Falls State Park. Follow the AT north until you hit Wayneboro. Campout at the trailheads. What more could you ask for??? Use ridewithgps and map out the route from Tampa to Amicalola and then follow the highway north to Waynesboro. I have a feeling that as long as you make sure and hit Avoid Highways any route you try to plan between Amicalola and Waynesboro will flat out parallel the AT. For my trip last year...initially...I was going to camp out night one at the Bennington, VT trailhead and then follow the AT south clear down Duncannon, PA. Wasn't what I did, after night one since I had completely changed the route but I did use Bennington for night one and I have bike camped at Clarendon Gorge trailhead up around Rutland as well. If you are going to be going to the trail you might as well use it. Do the initial click and point on Amicalola and Waynesboro and then set a few other point and move the route around to see what it shows that might be flatter. Remember one key thing about the Appalachians, if you stay to the east you stay flat...flatter...if you go to the west watch out be prepared for big time climbing. Get your route over toward Charlottsville not over toward TN.