I am afraid these people may have gone out of business. Here's what I have:
Small Potatoes, LLC
Premier Private and Corporate Catering
Natural, Farm-Fresh and Handmade
912 Conestoga Road, Rosemont, PA 19010
T 610.525.2394 F 610.525.2395
Looks like their website has disappeared as well. I used them for a party that was similar in scale in 2007 and was really happy with them. They had optional waitstaff as well. Fair prices, good food, and they even helped with a special diet restriction.
Sorry I don't seem to have anything more current. Seems like for all the *talk* about green/organic/locavore food, there are few people actually in the business of providing it. Maybe some people involved with SF would know? Or an organic restaurant?