American Memory - This site provides free and open access through the Internet to written and spoken words, sound recordings, still and moving images, prints, maps, and sheet music that document the American experience. It is a digital record of American history and creativity. These materials, from the collections of the Library of Congress and other institutions, chronicle historical events, people, places, and ideas that continue to shape America, serving the public as a resource for education and lifelong learning.
American National Biography Online -- Includes biographies of over 18,700 American men and women from the founding of the country to the present.
From Revolution to Reconstruction - Originating in the Netherlands, this website is dedicated to the pre-World War I history of the United States of America. Many primary sources are available at this website.
Library of Congress - An outstanding and invaluable site for American history and general studies. Contains primary and secondary documents, exhibits, map collections, prints and photographs, sound recordings and motion pictures.