There‘s so little activity in this subforum I rarely scroll down far enough to see the most recent post. In case the OP hasn’t already learned this there is a club in Kalispell called Flathead Valley Brewers. I haven’t found any contacts or other info, though.
EDIT-I did find a FB group for Flathead Valley Homebrewers Association. It’s private and I didn’t ask to join but I noticed it only has 9 members.
I'm not on FB but I will keep them in mind. I'm always surprised there are not more home brewers in NW MT since we have a lot of craft breweries around. I guess that explains the lack of brew supply shops.