I'd love to work with persimmon, too, if it's a bonsai-friendly species. I like the idea of working with local material. However, I have yet to see any for sale. The only thing I'd suggest is to try your state forestry service. Ours in Kentucky sell (to KY residents only) 100 12" persimmon seedlings for something like $30 or $40. Good deal if you have the space to let them develop a year or two.

Here is a link that might be useful: Picture of a Persimmon Bonsai