There are now quite a few US growers who are producing organic hops, although some of them might not yet have any organic crops to sell. In addition to the link above (4 yakima valley growers, who are all also large conventional growers), there are several member growers at the AOHGA: http://www.usorganichops.com/AOHGA/growers.html. Also, New Zealand has been the largest organic producer in recent years. I think Hopunion brokers these in under contract, but they can also be contracted directly from the New Zealand Hop Board.
If you are looking for small quantities for current use, I may have some extra 2010 certified organic hops to sell. PM me if interested.