The Library of Congress Civil War Map collection can be found at the link. It has an excellent collection of North Carolina maps, some of which are shown below. In addition, its search function is very easy to use.

Fort Anderson 

Coastal NC- showing inlets north of Wilmington

Gunboat Attacks on Forts Strong and Lee during the Wilmington Campaign

Bald Head Island

Fort Fisher

Wilmington Field Fortifications

Fort Johnston

Hatteras Inlet

Oregon Inlet

Roanoke Island

Fort Macon- Beaufort Harbor

Fort Macon- entrance to Beaufort Harbor

Siege of Washington