http://medicine.yale.edu/ - type PCR guide into site search box
http://www.protocol-online.org/- type PCR into site search box and select Molecular Biology: PCR
http://www.horizonpress.com/Select advanced search and use Search our information resource pages to look for The Jump Station. There is lots of PCR information here including programmes for designing primers
http://nobelprize.org/- type PCR into the site search box. This takes you to pages on PCR and a game based on the method.
The history of PCR: Smithsonian Institution Archives, Institutional History Division Sambrook, Joseph, and David W. Russell (2001). Molecular Cloning: A Laboratory Manual, 3rd ed
Mullis, Kary (1998). Dancing Naked in the Mind Field
Rabinow, Paul (1996). Making PCR: A Story of Biotechnology.