I've been listening to Myllärit for over ten years now. They're REALLY good, playing Finnish folk with modern-day rock instruments and folk instruments. The band that I've recently fallen in love with is Gjallarhorn (Swedish-speaking Finns). The violins and the vocals are absolutely tranquilizing (see video below). Most of the other folk I hear..I see live performances at Scandinavian festivals in Seattle, random compilation CDs, and stuff I randomly stumble upon while on YouTube.
Gjallarhorn - I Riden Så (Ye Ride So Carefully) - YouTube