Lucy,

You might try Barry Webb's site called the Organic Gazette and who moderates a very active gardening forum. Of course, Garden Webb has its own UK Garden Forum under the European Garden Web umbrella.

I recall that their are some community gardens on your side of the Pond along with traditional allotments which tend to be larger pieces.

Here is a link that might be useful: Organic Gazette

Yes they are called allottments

There are a lot of resources for people looking to start community gardens in the UK.

Your first step could be to contact your Local Authority who will be able to tell you about any exisiting sites and what support or grants may be available to help you set up a new one.

Allotments are parcels of land that are rented to individuals to grow food. There is often a waiting list of years in many locations.

If you are based in London, there is an organisation called Capital Growth. I found them to be very helpful.

Here is a link that might be useful: Capital Growth Website