Check out General Panel Corp. They have a plant in Johnson City TN, which is just down the road from western NC.
They also mfg Logix ICFs at the same plant. Depending on your home size, you might be able to combine the two products on one shipment, and save some freight costs. I've used their products for several years and find them to be of very high quality.

When are you moving to WNC? I live in Asheville and represent a company called Eco-Panels. I've spent the last 4+ years researching high performance buidling systems focusing mostly on SIPS. For the last 15 months I have been directly involved with new residential building science while providing Energy Star (H.E.R.S rater) and NC Healthy Built Home certifications. I met the new owner of this company at a Green Building Function last year and it was the most impressive system I've seen to date, so I decided to join the company and represent a product I will build my next house out of. Although I am a fan of sips and Energy Star recommends sip systems, not all sips are created equal. For example, Eco-Panels has the best thermal boundary in the industry and this weekend at the Asheville Home Show we will be dispaying a roof panel that integrates solar thermal technology into the assembly. Our new website will be going live in the next two weeks providing a significant amount of information and resources for everyone interested in high performance building systems (mortgage info, tax credits, scientific research, technical info etc). We are working with some of the leading scientists in the region and nation. Let me know if I can help in any way.

http://www.hitechconstructionproducts.com/