Jillie- you said you ask for donations on facebook. Can you give examples of what companies you have sent facebook messages to that have sent you items?
I'm not sure how big you're thinking but we were able to get Best Buy to donate a Kindle Fire and we used that as our raffle item at our last auction. We charged $5 per ticket and made just a bit over $500 on the raffle alone.
Anyone have any ideals on how to get 1 big raffle prize that people would be willing to try for without asking a PTO member to come out of pocket to buy it?