Legislation
http://www.legislation.gov.uk/

Case law and legislation and much more
http://www.bailii.org/

Supreme Court for decided case in the Supreme Court as well as a link to House of Lords judgments since 14th November 1996.
https://www.supremecourt.uk/decided-cases/index.html

Privy Council decisions (predominantly since 1999)
http://privycouncil.independent.gov.uk/judicial-committee/judgments/

Law Commission Reports and Consultation papers
http://www.lawcom.gov.uk/

Official documents (Command and House of Commons papers)
http://www.official-documents.gov.uk/menu/browseDocuments.htm

European Union Law
http://eur-lex.europa.eu/en/index.htm

EU Contract Law
http://ec.europa.eu/justice/contract/index_en.htm  

General Links
http://www.kent.ac.uk/lawlinks/

Legal abbreviations index
http://www.legalabbrevs.cardiff.ac.uk/