Co-operatives UK
National membership and campaigning organisation for co--operatives. Site includes directory of members, information about co-operatives and how to start one.
http://www.uk.coop/

Co-operative and Community Finance
Loan finance for co-operative projects and community groups.
http://www.coopfinance.coop/?content=links

Financial Services Authorities - Register of Mutual Societies
The FSA is responsible for the registration and regulation of mutual societies including many co-ops.
http://www.fsa.gov.uk/doing/small_firms/msr