Got a citation to law report? The first place to check is the Cardiff Index to Legal Abbreviations (U.K.) You may also consult:
Prince’s Bieber dictionary of legal abbreviations: a reference guide for attorneys, legal secretaries, paralegals, and law students. Mary Miles Prince. 6th ed. Buffalo, N.Y. : W. S. Hein & Co., 2009.
Trustee Reading Room Reference (DR): Ready Ref. Firestone KF246 .B46 2009
Got a citation to a statute?
Statutes are cited by regnal year and Parliamentary session up until 1963. Lists of regnal years can be found in many legal reference books and at http://www.law.harvard.edu/library/research/guides/int_foreign/uk/regnal_years.pdf
Chronological table of the statutes. London : H.M.S.0., c1979.
Trustee Reading Room Reference (DR): Firestone KD142.3 .xC5 1979
This lists all statutes in order, and is very useful for following the subsequent history of a statute as it is repealed or superseded by later legislation. Citations can usually be tracked down in sources listed under Statutes or, as bills, in the House of Commons Parliamentary Papers -- search by Parliamentary session and using keywords from the title of the statute.
Looking for a statute by title? Many statutes are known by "short titles" or by the names of their sponsors or of the place where they were enacted. Consult:
Manual of legal citations. London, 1959 [i.e. 1960]
Trustee Reading Room Reference (DR): Firestone KD400 .xM3 1959
Or consult the Short Titles Act 1892, Short Titles Act 1896, and the Statute Law Revision Act 1948, in House of Commons Parliamentary Papers.