There is a national organization for community gardens, I do not remember the exact name of it but it may be on the list of non-profit organizations listed here at Garden Web. They would be the best place to start.

You can also check with the local Master Gardener extension office for resources, they can be quite helpful.

"Plant A Row For The Hungry" is another organization that has roots in community gardening.

I hope this helps you some.

Hi Erica - I am a community gardener in Vancouver, BC. Good luck with your project.

Here is a link that might be useful: Vancouver Community Garden Report

Hi . I think that you will find that many people garden for food seriously in Sullivan County. They fence out deer, spray predator urine around, hang hair balls around...
There are farmstands. You will not find it difficult to get manure and hay. Perhaps you could find people who cannot do all the work that it requires, but can pitch in. Also there are some serious garden clubs there and in Ulster County.