The Churches of East Anglia - Simon Knott's comprehensive website was the inspiration for this one. He writes with dry humour, and his site is excellent both for browsing and as a guide for exploring the counties of Suffolk and Norfolk. Very highly recommended.
John Whitworth's excellent Essex Churches site is gradually providing a photographic record of all of the churches in that county.
The Leicestershire & Rutland Church Journal
Chris Jones' site.
John Vigar's Kent Churches site.
The Churches Conservation Trust protect over 300 redundant churches around the country. They have eleven churches in the county - very well maintained they are, too.
The William Dowsing Site - a splendid, if occasionally depressing, resource as it has Dowsing's journal online. The Nasty Puritan is most famous for the destruction he wreaked in his native Suffolk, but he came to Cambridgeshire too. The quotes from the Journal used on this site are all extracted from Trevor Cooper (ed.), The Journal of William Dowsing: iconoclasm in East Anglia during the English Civil War , Woodbridge, 2001'.
The wonderful Corpus of Romanesque Sculpture in Britain and Ireland site has now covered Cambridgeshire, and a damn fine job they have done too. The site covers all examples of romanesque ("Norman") sculpture in the county with plenty of photographs.