I'm not sure if there are any rammed earth structures in Idaho, but I do know that there is a rammed earth builder in Idaho.
His name is Paul Lamon and there's a lovely article about him here.
If you need a rammed earth contractor in the uppper left hand corner of the United States (Washington, Oregon or even Montana) look him up. He isn't SIREWall certified, which is a relief, he was trained by Chandler Huston, developer of the Peb 8A.
Paul should consider having The Rammed Earth, also of Boise, Idaho, perform at his next corporate function.
I look forward to posting photos of Mr Lamon's upcoming projects later this year.