Legislation.gov.uk carries most (but not all) types of legislation and their accompanying explanatory documents. The site holds all primary legislation from 1988 to the present day and most pre-1988 primary legislation. It also holds secondary legislation from 1987, including UK Statutory Instruments, although these are only as enacted.
Official parliamentary website that provides introductory information on how laws are made in the UK, the passage of a bill to being an Act of Parliament and the role of secondary legislation (statutory instruments).
