First off, I LOVE Peter Pan. That would be my dream party!! haha
Okay, as for party ideas...
I know that finding actual Peter items is far more difficult than Tinkerbell items. I think on certain occasions, I have seen Peter Pan items here (in Memphis) at a Hobby Lobby and Party City. I don't know if the same will apply for you.
If all else fails, a themed dress up party might be cute? Peter, Wendy, Lost Boys, Pirates, Mermaids, Indians.
You could decorate the house in "Peter Pan colors" like green streamers and everything. Themed foods and cake would be cool, too.
Also, this might help:
http://www.birthdaypartyideas.com/html/peter_pan.html
It's party ideas from people who have had Peter Pan parties before. They say what they did, how they did it, and the age of the special Birthday Child.
Good luck, and I'm sure it will be a blast!
