The archive collections of the Devon Record Office, the local studies materials and the Devon and Cornwall Record Society collection from the Westcountry Studies Library reading room, are now housed together at the Devon Heritage Centre. Includes parish material, hospital and school records and other records relating to Devon, Dorset, Somerset and Cornwall. There are guides and catalogues.
http://www.devon.gov.uk/record_office.htm
This site has searchable databases of transcribed parish registers plus muster rolls, hearth taxes, apprentice indentures and much more.
http://www.cornwall-opc.org
Census transcriptions for England, Scotland and Wales 1841-1891. Not yet complete so check the coverage for the county of interest. Coverage is particularly good for Cornwall and parts of Scotland.
http://www.freecen.org.uk
Online information includes Comprehensive Gazetteer for England and Wales 1894-5 and parish registers for some counties particularly Cornwall and Derbyshire.
http://www.uk-genealogy.org.uk