I have been anxiously awaiting this resource and I am so happy that it is finally here! Please see the following website for what I believe is the only private tDCS treatment clinic in the U.S.
www.transcranialbrainstimulation.com. It is operated by Dr. Jim Fugedy who is arguably the best tDCS resource in the country. While two research institutions offer tDCS treatments, they are still basically research oriented, which I believe limits their ability to apply the treatment to many forms of chronic pain.