Delaware National Coastal Special Resources Study Act - Directs the Secretary of the Interior to conduct a special resources study of the national significance, feasibility of long-term preservation, and public use of sites in the coastal region of Delaware. Requires such study to include an analysis and any recommendations of the Secretary concerning the suitability and feasibility of: (1) designating one or more of the sites along the Delaware coast as units of the National Park System that relate to the themes described in this Act; or (2) establishing a national heritage area that incorporates the sites along the Delaware coast that relate to such themes.