There are a bewildering variety of different organisations out there who can help with the history of your home. Here are a few links that may be worth following up:
Ancient Monuments Society – these guys campaign for protection of old places – not sure if there is any money available though
Architectural Heritage Fund – this is more for Scottish help
British Association for Local History – These guys will help you learn more about your house
Churches Conservation Trust – Very big, work on church conservation – good if you own one and need help
Drystone Walling Associatio – I always wanted to do this for a living – no stress, just lovely old walls
Listed Property Owners Club – Good point of contact for insurance and finance on old buildings
SPAB (Society for the Preservation of Ancient Buildings) – Jolly nice chaps, except they actually speak to the PCA 🙁