I think you'd have even more people interested if you could get some of the performers for guest appearances and the thing is is if you only do a one day convention then might not be too hard. If you were to do like a two day thing you could have different performers on the 2 days it's held. And you'd need to get good publicity for it somehow where ever you decide to have it. I don't really know a whole lot about these things but I'm sure don't you have to get permissons or something from like Seasame Street workshop and Disney etc?