I await an answer from someone also. Their Asarum and Epimediums look great, and they are about the only source of Hellebore Thibetinus around. I have been mulling over this for nearly a year.

George

You will need a Plant Import Permit, PPQ587, issued by APHIS/USDA. Application can be made by mail or fax. There is no charge for the permit. Chen Yi requires only the Permit number and expiration date. (The permit is good for 5 years.) The website for a printable application form is listed below. Be sure to list as many Genera/species of plants as you can and are interested in, on the form. If you plan to order several species of a Genus, list the Genus name and instead of a specific epithet, just list: species. Necessary, when the species is unknown!
Rb

Here is a link that might be useful: APHIS/USDA Permits