Here are some resources to help with contracts:

I have used both of these sites. But if you are keen to be totally legal then i advise you take advice from a solicitor, lawyer or attorney.

http://www.legalcontracts.co.uk/contracts

http://www.legalcontracts.com/

 

In the UK the Federation of Small Businesses offers a free legal helpline with membership.  The FSB is a business organisation specifically for small businesses and offers a range of services with membership.

http://www.fsb.org.uk/