Elinor; I do hope I can help you but as other mudcats have mentioned. your's is a subject that is both wide and somewhat confusing. Libby Cotten would fall in to the category as would Maybelle Carter, Mary Larkin Judy Collins, Triona Ni Donmhail, Delores Keane and Lorena McKennitt(sp). Again, unfortunately traditional to the purist mean anonymous although by law any tune that has been in public domain may qualify. Generally this means in a legal sense that whoever wrote the song has been dead for at least fifty years and there are no copyrights in force. Good luck in your search and if I can be of further help please don't hesitate to contact me.