Well, you NEVER have too many, so here are a few without much comment. Just explore.

http://parlorsongs.com/ My favorite.

http://midiforum.com/brtubb/ No, this one's my favorite.

http://www.perfessorbill.com/index1.htm Uhh, OK, I give up.

http://primeshop.com/midilist.htm I will comment that while this one is good for ragtime tunes, it does not have lyrics.

Hey, Tiger, looking at your test thread made me think you would be here, and reminded me to collect some of my favorites, too.

Oh, one more that I forgot, but shouldn't have. http://www.contemplator.com/folk.html Lesley's site of REALLY GOOD STUFF!