Gap Year Sponsorship?

In summer 2013 (yes I know I'm an early planner) I want to go to Camp America and hopefully help with children who are either disabled or inpoverished, other wise just every day children. After than I want to go on a Contiki tour of America (google it) and all in all it will be �3309 without insurance and spending money. I have a part time job but I was wondering if there are any websites/businesses/charities that may sponsor me? Thanks