http://www.dsa.gov.uk/ - DSA (Driving Standards Agency) website containing useful information about the Theory Test and Practical Driving Test and how to book them online.

http://www.direct.gov.uk/en/Motoring/index.htm - Government website containing useful info relating to all things motoring, well worth a visit.

http://www.theory-tests.co.uk/ - Official DSA Practice Theory Tests.