A hundred bucks is the I-Sponsored-an-Artist level. You get art! Well, you're not getting the original, but you will get a copy of one of the illustrations signed by the artist!!!! (By copy, I mean a print out.)
Hmm. We need a premium level, don't we? How about this, for $400, I will come to your event and read a story. It could be a cabaret, a benefit or a private party. Tack on another hundred, and I'll read two!
(I would offer something on the thousand dollar level, like I'd come clean your house in the nude, but I'm not very good at cleaning and I don't want you to feel cheated)