Whitelady, try ancestry.co.uk (I understand it is free at some local libraries). Use ancestry to look up your family on the census returns, which should be available from 1901 - 1841. You will need findmypast to look up the 1911 census.
If the farm is local to you, contact your local records office and go and look at the parish registers.
You can also use freebmd.org.uk (free site for civil registration - not complete), findmypast.com (subscription or pay per view for the full index of civil bmd registrations), familysearch.org (free site for 1881 Census and some parish registers - again incomplete and treat with caution because some are entries submitted by the members and not always correct), freereg.org.uk (again free site for parish registers but only very limited so far), you may also find some information on the pro.gov.uk - always worth doing a search there - I have turned up a number of family documents and wills there.