I seen your other post about the beaverhead-deer lodge national forest.
That national forest consists of several mountain ranges. The best advice that I can give you is to pick a mountain range and research it.
I bought a book. I believe the title is: elk hunting the best montana public lands. (Or something like that, don't have it in front of me) by Jack Ballard
It gives information on all the ranges, national forest access, all that. It was a good investment, I thought. Then I bought a montana sportsman atlas. And don't forget Google Earth.
With those three tools and the montana fwp website, you should be able to narrow down an area.
I've been going out there four years and just finally starting to get my spots picked out. But that's kind of the fun part, learning something new every year. I guess I look at it as an investment. Sooner or later, it'll pay off!! Plus, I get all them years of the experience.