Thanks Axilrod! I'm headed to northern Montana, so city lights won't be an issue
Ahh I envy you, that's a great spot for astrophotography. During the winter visibility is high but the brightest parts of the Milky Way don't really get too far above the horizon. In the northern hemisphere the summertime is going to give you the best view of Saggitarius (where you want to aim for those awesome pics of the spiral arm), but it's still worth giving it a shot in the winter.
Definitely download Stellarium, it's an absolute must and will show you where everything will be at any given time. When you launch it toggle "atmosphere" to off (hit "a" on your keyboard), other than that it's pretty straightforward. Post some results after you give it a shot!