Beware, anyway - lots of bands of that genre are truly racist!
However - there's some great stuff out there!
Real fun are e.g. Korpiklaani from Finland, using accordeon, flutes&whistles, violin and Estonian bagpipes (ancient Finnish pipes were alike): http://korpiklaani.com/
Then, You have impressive stuff from France: Bran Barr, Aes Dana, Valuatir, Astaarth and, my favourite, Hantoama - the last being truly FolkMetal, the others some BM-Stuff, all of them with heavy and high-quality use of different types of cornemuses.
In spain, there's some good stuff as well. I personally like "Üser Ne", rather Goth-Metal with great use of Gaitas: http://www.metal-archives.com/band.php?id=6513
Also the Russians have quite something to offer - check out e.g. "Pagan Reign": http://www.myspace.com/paganreign
The lyrics are - well - hard to take seriously, but the music's great!
Also great stuff: "Znich" from Belarus - BM based on some trad tunes, using trad singing, fiddles and Belarus bagpipes.
...but my absolute favourites in this genre come from Estonia - "Metsatöll"! http://www.metsatoll.ee/index.html
If You love Metal - don't miss them! If You love bagpipes - don't miss them! If You love both - they can't be beaten! Excessive and truly fine use of Estonian Torupill combined with really intelligent Metal - and, as You might expect with truly intelligent people, they don't take themselves too seriously...