ACA routes: Underground Railroad route (http://www.adventurecycling.org/rout...ndrailroad.cfm) to either the TransAm Route (http://www.adventurecycling.org/routes/transamerica.cfm) then east on it to the Atlantic Coast route (http://www.adventurecycling.org/rout...anticcoast.cfm), Or the Underground Railroad route to the Northern Teir route (http://www.adventurecycling.org/routes/northerntier.cfm) to the Atlantic Coast route.

ACA has all the maps (for a price) and they are very logistically informative. They'd get you close. The Northern teir would probably be the most direct.