you might be interested in this co-op/buying club already operating in NJ http://www.purpledragon.com/about.html
Meli65 posted this link after I enquired about wanting to start a buying club in the Cleveland, OH area, which we are tring to do if we can get enough people together. There are also lots of online groups for stuff like sewing supplies, gardening stuff, fabric, etc. If you do a search on yahoo groups you'll find lots for non food co-ops. If you do want to start you own, tho, the northeast site already mentioned by elismama has a wealth of info.