Pre -census sources that are easily searchable are the IGI on familysearch.org as above, they cover parish registers of baptims and marriages and sometimes burials that members have added. The entries are included in 2 ways, the LDS library has purchased the primary or secondary sopurce material and transcribed and indexed it, or a member of trhe LDS church has submitted their research for inclusion. Parish registers began in 1583 and were overhauled in 1597, if a church existed on or after those dates their regsiters were systenatically included as and when the lDs church processed them into the index, originally they were indexed by county and now they appear on your search screen alphabetically by surname in alphabetical by county and then date order.
Other sources that vary in acessibility are wills pre 1858, many counties have these already indexed by surname and you can search their database quickly for free and take a ganble of the right one, google cheshirewills to see how their's works it's only £3.50 a copy and they send actual photocopies of the will folios. Brillliant source.
Land Tax Assessments can give info in tenants and landlords and are included on the familtsearch pilot from the LDS for alot of counries. Your local CRO website will cover these.
The greatest sources are the Quarter Session records each CRO has available, try the access to archives site, it is very detailed and will lead you to lots of records you did not know about.