Civil War Online Document Library  
   Subscription-only searchable databases specializing in history, genealogy, classic literature, and general reference material related to the US Civil War.
   http://civilwar.scbbs.com/

The Library Company of Philadelphia  
   Specializes in the history and background of American culture from the colonial period to the end of the nineteenth century; with an overview of the collection, access to the online catalog, and general information.
   http://www.librarycompany.org/

US Holocaust Memorial Museum Library  
   Resources for family history and other research as well as access to the online catalog.
   http://www.ushmm.org/research/library/

Brooklyn Historical Society Library  
   Information about collections and exhibits, publications, membership, educational programs, and volunteer opportunities.
   http://www.brooklynhistory.org/library.html