Here is a list of useful links:
CLEAR Cannabis Law Reform, the UK's largest membership-based cannabis policy group. CLEAR campaign for medicinal cannabis on prescription and regulated access for adults.
Marijuana.com is the leading cannabis related message forum and news site.
Informing the public about cannabis
Cannabis - The facts
Petition - Make the production, sale and use of cannabis legal.
Potsmokersnet.com. We are a World Wide list of the best 420 sites on the planet.