According to A Brief History of Basic Intelligence and The World Factbook, "The National Intelligence Survey [NIS] is an invaluable publication which provides the essential elements of basic intelligence on all areas of the world.... The Factbook was created as an annual summary and update to the encyclopedic NIS studies." The World Factbook contains a variety of information on countries of the world, including maps that are available in jpg and pdf format.
The World Factbook is in the public domain. The link above is to the latest version on cia.gov. The 2001 version has been archived here, on Polisource.
The U.S. Department of State's Background Notes provides less statistical information on countries of the world than the World Factbook, but reads more like an encyclopedia. It also includes dates of updates.
Background Notes is public domain and Polisource has archived an old version here.
Polisource's U.S. State Songs & Flags page includes public domain versions of state songs, lyrics and flags. Whenever possible, links are included to sites that legally publish state songs and lyrics that aren't shown on Polisource. Links to official websites of each state will be added eventually.