National Archives Kew, London
London Met Archives
Hansard Online
Churchill Archives
Military Intelligence
Mass Observation Unit WW2
MOI Project, University of London
Home Intelligence Reports WW2
BBFC British Film Censors
Talking Pictures TV channel
UK Data archive (Essex University)
BBC Written archives
War Museum Archives
War time social surveys
USA Archives
European Union Archives
France Archives
Office of War Information USA
Archive Grid (good for USA databases)
Royal Historical Society
BBC Screen archives
JSTOR (digital library of sources)