There are no doubt PR professionals in Missoula. I have been reading your e-mails for some time and love what you do. Others do also. Word of mouth is a great way to start spreading the good news of permaculture (as are the playing cards) but at some point you have to reach people who may not know the people you know. With PR professionals, you pay for their time. They should put a plan together for you, write up articles and news pitches for you, and reach out to gardeners, trade publications for alternative lifestyles, gardening, etc. to get the folks already thinking about life differently - who may not know about your blog or the cool stuff permies are up to. It's good to start where you are - because then you can meet with your person, they can take photos, and see what they can do locally for you first.
https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=Missoula+montana+public+relations. But if you can't find like-minded folks where you are, I can always help.
You will get A LOT more bang for your buck with PR than advertising. Any advertising you do can support the PR already in place.
All the best, and GO PERMIES!