Can anyone send me a building contract.....?

Some office supply stores have generic contracts for many things..

Construction contracts are quite specific to the laws which apply to the project in your country, state, shire or whatever.

The contract terms will likely be different for an alteration to a dwelling than they are for an alteration for an office building (usually as a result of consumer protection laws).

If in Britain, I would contact the Royal Institute of British Architects, or a member of that association and obtain some guidance. Alternatively there will be a Master Builder's Association in Britain giving you a slightly opposing perspective. Chances are high that together they have developed a collaborative contract for use by their members.

There are many different types of contract, for numerous different scenarios. Try www.ribabookshops.com. They should be able to direct you to what you need.