British Music Information Centre
Organisation documents and promotes twentieth century British composers.
Timothy Salter's scores and recordings are available for study at BMIC.

British Music Society
Publishes various journals, subscription publications etc.
Website is large and full of interesting material. Members are interested in British composers from 1850 - present.

Bath University Gateway for Humanities (Music)
Useful resource with many interesting links.

Classical Music UK / Orchestranet
Another large site containing pages on many different orchestras, ensembles and organisations.
Part of the Classical Music webring.