Here's a couple of sites that may help. This one is a survey, but the authors could be contacted for some info on native plant nurseries.
http://www2.montana.edu/yzadegan/index.asp

The link below mentions several native plant nurseries in Montana.

You could also try a Google search on "Montana native plant" to find the links for any native plant organizations in Montana. They could provide information on sources of native plants in Montana.

Here is a link that might be useful: Some Montana Native Plant Nurseries

Put the wrong link in the message above - here's the right link:

Here is a link that might be useful: Some Montana Native Plant Nurseries

That's a great site! Just what I was looking for, only better! I tried to forward it to her, and in case it didn't go sent a separate email to come here. I keep trying to get her hooked on GardenWeb, but I'm not sure I'm successful. Of course at this time of year she's canning and getting things in the greenhouse if they're not in already, and doing what she can to prepare for the winter that's about to hit. Hard for me to imagine she's already had frost when we are having trouble finding nights below 80. Thank you so much!