Yorktown & Willamsburg, VA if you like historic places
www.yorkcounty.gov/tourism .
www.colonialwilliamsburg.com. Close to the beach but you'd need to drive. Virginna Beach is very touristy. I personally love the Outer Banks of NC myself - and even some of the smaller barrier island places further south - and would suggest many places there. Cape May, NJ is nice too but probably to far north for you. Both Chinquoteague and Assateaque islands are great.
www.chincoteague.com www.assateagueisland.com