Many important sources and historical documents are available as internet archives. Below are some of these documents and sources that I have found especially useful or interesting. To access these documents or sources, please cut and paste the URL onto your browser. Press on the Contact link to the left if you would like me to include a certain site on this page.
The History Department of the U.S. Military Academy at West Point offers excellent maps for the Chinese Civil War at The Chinese Civil War Maps or by cutting and pasting the following onto your browser: http://www.dean.usma.edu/history/web03/atlases/chinese%20civil%20war/chinese%20civil%20war%20index.htm
The CIA World Factbook on China is at http://www.cia.gov/cia/publications/factbook/geos/ch.html
From the National Security Archive
China and the United States, from hostility to engagement, 1960-1998 are at http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB19/
The United States, China, and the Bomb are at http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB1/nsaebb1.htm
The United States and Chinese Nuclear Weapons Program, 1960-1964: companion documents for an International Security article are at http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB38/
The Chinese Nuclear Weapons Program: Problems of Intelligence Collection and Analysis, 1964-1972 can be accessed at http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB26/index.html
The Sino-Soviet Border Conflict, 1969: http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB49/
Reconnaissance Flights and Sino-American Relations 1969-1970: http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB41/
Secret Documents on "The Opening of China" Previously Secret Documents on Henry Kissinger's Secret Trip to China (1970-1971) can be found at http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB66/
New American and Chinese Documention Leading Up to Nixon's 1972 Trip are at http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB70/
Record of Conversations between Richard Nixon and Chinese Premier Zhou Enlai: http://www.gwu.edu/~nsarchiv/nsa/publications/DOC_readers/kissinger/nixzhou/
The completely declassified documents on Nixon's Trip to China are at http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB106/index.htm
Declassified documents on Tiananmen 1989: http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB16/index.html
Deng Xiaoping, Selected Works can be read at http://english.people.com.cn/dengxp/
Mao Zedong, Selected Works are available at http://www.etext.org/Politics/MIM/classics/mao/ Here is a different arrangement: http://www.marxists.org/reference/archive/mao/selected-works/