I have found one of the internet old style Lithuanian music.
Lithuanian (I'm am not shure is it same in Latvia) has very special old style songs, which we call "sutartine". The word "sutartine" is from word agree/arange. The aim of the songs is that same simple texts are singed in diferent time. This is very very old type of folk songs.
Better listen, than read :)
With older clothes:
Some views of old Baltic pagan rituals with songs
Old instruments are not for museaums only :)
Kankles (one of the oldest Lithuanian music instrumens)
some more bells (he better woundn't sing :D)
Some new traditions? :D