The Civil Procedure Rules are available at the Department For Constitutional Affairs. Essentially, they are the rules by which all court staff ( judges, solicitors and barristers work by). It is essentially a rule book. More information is found on Wikipaedia.
The Civil Procedure Rules (CPR) govern the way in which court cases are conducted in England and Wales. They were introduced in April 1999 with the aim of enabling courts in England and Wales to deal with cases justly and streamlining the civil justice process by resolving as many cases as possible without resorting to court proceedings. The Civil Procedure Rules replace the Rules of the Supreme Court 1965 and County Court Rules 1981.
The Blue Book is also available for purchase from the online TSO bookshop.