Here are a few ideas:
Kiptopeke SP on the lower Va. Eastern shore, Chesapeake bay beaches, boat ramp, fishing pier are in the park. Full hookups available. Been there many times, nice place.
Assateague SP on Maryland Eastern Shore, not far from Ocean City. I`ve been there but never camped there and have reservations in the H loop for August, the only electric loop in the park and very hard to get reservations for, they book up a year in advance. There are non electric sites still available but they will go soon as well. This CG is right behind the duneline, so a short walk to the beach and a short drive to the OC attractions.
Tall Pines Harbor on central Va. Eastern shore. This is a nice private CG with many themed weekends throughout the season. Waterfront sites are available but a bit pricey, they overlook the Pocomoke Sound which is part of the Chesapeake Bay.
Pocomoke River SP in Maryland. This park is located on the Pocomoke River. Wooded sites, nice SP with many river activities available. Not on the Chesapeake, about a half hour from OC and the beaches.
Janes Island SP near Crisfield Md. Some waterfront sites available, they are on a tributary of the Chesapeake bay with the bay only a few minutes away. Theses Marlyand parks have electric only, no water or sewer.
Cherrystone CG. Another private CG overlooking the lower Chesapeake Bay, many family oriented activities there. Also considerably more pricey then the State parks as expected.
These are just a few ideas, I have been to them all. There are several private CG`s on Chincoteague Island and near Ocean City as well that I have not been to yet.