The Sleep Inn has a couple different conference rooms you can reserve for a fee, which varies depending on the room size. The Guesthouse Inn (now Fairbridge I think) has a small conference room as well. They used to not charge a fee for it; not sure if they do now or not.
Range Riders Museum has a community hall with a kitchen area. I believe they may charge a small fee for use, but its nice especially if you like a little western flair.
Tongue River Winery would be a nice option as well, especially for a more intimate setting. They have a nice community area that has tables and chairs and a view of some of their grape growing areas. Usually Bob and Marilyn don't care if you bring in your own food and beverages, provided you don't bring in your own alcoholic beverages if you desire to have that.