I second the Carol Deppe recommendation! There's also some great (albeit more general) insight about selecting varieties for resilience in her other book, The Resilient Gardener
, which is available at the Missoula Public Library.
Also, there's a seed swap coming up, where I know people will be trading their own varieties specific to Montana. Here's the listing:
Missoula Seed Swap
WHEN: Feb 15, 4 to 7 pm (NOTE NEW TIME)...
WHERE: Stensrud Event Center, 314 N 1st W.
Potluck snacks. Hosted by the Inland Northwest Permaculture Guild