Modern Records Centre housed at Warwick University holds many original resources from Trades Unions and local Labour Parties and individuals.
University Library, Coventry CV4 7AL

National Museum of Labour History The People's History Museum in Manchester holds the national records of the Labour Party and the Communist Party together with papers of many other figures.
103 Princess Street, Manchester M1 6DD

University of Hull archives contains some local Labour Party records together with that of individuals. This link takes you to the listing. See John Saville, The Labour Archive at the University of Hull (1989).
Hull University Library, Cottingham Road, Hull HU6 7RX

Glasier papers
John and Katherine Bruce Glasier founder members of the ILP

International Institute of Social History
The International IISH in the Netherlands was founded in 1935. It is one of the world's largest documentary and research institutions in the field of social history in general and of the labour movement in particular. Links to International Association of Labour History Institutions from this site.

South Wales Coalfield Collection
The documentary records of the mining community of South Wales notably the South Wales Miners' Federation (The Fed).

Working Class Movement Library
the treasure of Salford. Holds records mainly of trade unions in the North West engineering industry.
51 The Crescent, Salford, M5 4WX