The TFO spey rods are pretty nice faster, stiffer 2-hand rods. They are a very good value for the money, although they are not in the same league as the top rods from the high end rod makers they are very good casting rods. They are fairly fast and stiff rods that don't bend into the cork unless you are really putting the wood to them so don't be surprised when you don't feel the rod "loading" down into the grip.
That said, they are very good casting rods that are more than adequate for someone getting into 2-hand rods and spey casting. The 9/10/11 Windcutter line you got for it is a very good match for the rod. I know there is at least one fly shop in Boise; but I don't know if they know anything about spey casting. I'd be surprised if there were no spey casters in Boise though.
However, there are folks up on the Clearwater (Redshed Fly Shop, one of our sponsors for instance) who sell and use 2-hand rods that could give you some instruction, and it is about 4 hours north of you. There are guides working the Clearwater and Grand Rhonde who use 2-hand rods that I'm sure would provide spey casting instruction to clients.
Also, Simon G. of RIO (one of the finest if not the finest spey instructor alive today) lives down the road 4 hours. He may offer spey casting classes in the Idaho Falls area; but I don't know you'll have to contact him via private message or email to find out. There are also other spey casters in the Idaho Falls area who probably teach spey casting.
Barring any of these options, the best thing for you to do is get RIO's International Spey Casting video or DVD. This video features Simon G. explaining and demonstrating the most common spey casts in a way that would allow you to get a basic understanding of the casts. Another good resource is John and Amy Hazel's Spey Casting video.
