Wow, how do you add quotes in this forum layout?!

And, ah, song lyrics… I don’t think I’ve ever actually translated folk songs (not seriously, at least), as it requires not only serious poetic talent (which I utterly lack), but also understanding of all the archaic and dialectic words the songs are filled with. Still, there was a great site with English translations of Serbian songs about Marko Kraljevic, which I sadly can’t seem to find at the moment, so I’ll add to Shaokang’s link also these quick Google finds, which include English translations of Serbian songs:
As for Bulgarian songs, I found this site (with mostly modernly popular songs, though it’s the first time I hear of the first one in the list, “Aishe”, unless it includes Gypsy folk too), as well as several booklets (with author songs from one woman, based on traditional folklore):
I also have a very nice old book with collections of songs, divided in various categories (heroic epos (yunashki pesni), voivode/haiduk songs, harvest songs, ritual songs, love songs, humour songs etc), which I might eventually try myself at, if it’s only about the meaning of the text, not the poetic steps. Then again, the internet has an even greater collection of them in Bulgarian itself (for those able to read at least Cyrillic), so I don’t really need the book:
http://liternet.bg/folklor/sbornici/bnt/1/index.html – Yunak songs
http://liternet.bg/folklor/sbornici/bnt/2/index.html – Haiduk songs
http://liternet.bg/folklor/sbornici/bnt/3/index.html – Historical songs
http://liternet.bg/folklor/sbornici/bnt/4/index.html – Mythical songs
http://liternet.bg/folklor/sbornici/bnt/5/index.html – Ritual songs
http://liternet.bg/folklor/sbornici/bnt/6/index.html – Love songs
http://liternet.bg/folklor/sbornici/bnt/7/index.html – Household songs
http://liternet.bg/folklor/sbornici/bnt/8/index.html – Labour songs
http://liternet.bg/folklor/sbornici/bnt/13/index.html – Folk songs
And many others on that site…

P.S. Oh, and there’s of course the Veda Slovena (phototypic editions, with parallel translation to French in the first one, from what I see), though its authenticity is under dispute (considered to be 19th c. creation by most scholars, especially in the West):