I live in Billings, MT, which is on the other side of the state, so don't have details on games near I-15.
But there are lots of small card rooms in Montana. All are small stakes because by law there is a cap on the pot of $300.
Here in Billings a few places have NLHD games certain nights of the week; and several places have no limit overs available and often turn into no limit games.
If you want detailed information, it would be helpful to list the towns you are interested in.
The following is a link to a MT government page which lists all the places licensed to have poker games. Not all of the places listed actually have games though.
http://www.doj.mt.gov/gaming/statist...8/mt_mtr36.pdf
-- Don