Foreign Relations of the United States:
The Foreign Relations of the United States (FRUS) series presents the official documentary historical record of major U.S. foreign policy decisions and significant diplomatic activity.
The US Presidential Libraries
Wilson Center, Digital Archive
The Digital Archive contains once-secret documents from governments (and especially the Soviet Union) all across the globe, uncovering new sources and providing fresh insights into the history of international relations and diplomacy. It collects the research of two Wilson Center projects which focus on the interrelated histories of the Cold War, and Nuclear Proliferation. The third link points to publications based on these declassified documents
The 20th Century British Collection of Newspapers
This is not a collection of all newspapers, but it does contain a sample of many London and provincial titles.
British History Online
For those of you interested in looking at the policies of the state – the crown and privy council, secretaries of state- and parliamentary debates, there are many available sources, although they are not always easy to locate
Political history resources
Contemporary Journals of the Houses of Commons and Lords, which summarise proceedings, although the summaries are pretty brief. There are also some sources which contain fuller records of parliamentary debates on the same page, for certain periods- when using these, make careful note of the nature of the source that you are using.
German History in Documents and Images
(GHDI) is a comprehensive collection of primary source materials documenting Germany’s political, social, and cultural history from 1500 to the present.
The Digital National Security Archive
The Digital National Security Archive contains the most comprehensive set of declassified government documents available.
The Parallel History Project on Cooperative Security
PHP provides new scholarly perspectives on contemporary international history by collecting, publishing, and interpreting formerly secret governmental documents.
The Harvard Project on Cold War Studies
The Cold War Studies program at Harvard University’s Davis Center promotes archival research in former East-bloc countries and seeks to expand and enrich what is known about Cold War events and themes.
Printed primary sources
An excellent collection of documents on the Cold War:
Mastny, V./ Byrne, M. (eds.), A Cardboard Castle? An Inside History of the Warsaw Pact, 1955-1991 (National Security Archive Cold War Readers , 2005)
Savranskaya, S, Blanton, T. and Zubok, V. (eds.), Masterpieces of History. The Peaceful End of the Cold War in Europe (CEU press, 2010)
Paczkowski, A., and Byrne, M., From Solidarity to Martial Law: The Polish Crisis of 1980-81 (National Security Archive Cold War Readers , 2007)
Hanhimäki, Jussi M., and Odd Arne Westad. 2004. The Cold War: A History in Documents and Eyewitness Accounts. Oxford, New York: Oxford University Press.
Judge, Edward & Langdon, John (eds.), The Cold War: A Global History with Documents, Pearson, 2010
William C. Wohlforth (ed.), Cold War Endgame. Oral History, Analysis, Debates (Pennslyvania University Press, 2003)
For Cold War history, the best way to find out what has been published on a subject is via the online Historical Abstracts (via EBSCOhost)
The Bibliography of British and Irish History (BBIH) is the most extensive guide available to published writing on British and Irish history.
There are also two journals dedicated to Cold War History