Montanan,
I don't live in Montana anymore, but I used to live up in the Flathead. Kalispell to be exact. Anyway, there is a great traditional club up in Libby that puts on two shoots a year. One is traditional/primitive only, the other is open to all bows. This won't help you this year, because the shoots are already come and gone. The trad shoot is in May, and the other in June. The club is Libby Archery Club. There is also a newer club in Troy, Montana, a little ways west of Libby, and they do a shoot or two, as well. I believe there is a shoot near Thompson Falls every year, as well. Not sure the date, but last time I went, it was in August. The Mission Valley Archers, out of Polson, do a Cabin Fever shoot in like April, near Polson, every year, as well. Another shoot I have been to once or twice was put on also in June, I believe, and it was located east of Missoula where Hwy 200 and Hwy 83 (Swan Hwy) come together at Clearwater Junction. Hope this helps.
I now live in Texas, and am having the same struggle as you, trying to make contacts and finding where the shoots are located. Good luck, and go bugle in a bull this September for me!!