There are some suggestions here:
//www.city-data.com/forum/boise...artment-2.html
If you do a search on "movers" and "moving companies" in the Idaho forum, you'll get several more hits. Good luck.
I've used these guys to get stuff from the East Coast to CA, and they were very good. It was a package deal, continuing a transport from overseas, so I can't tell you exactly what the domestic part cost.
www.flatrate.com/international
Have you tried asking your question in the CA forum?