Frankie Armstrong
Jean Redpath
Ray Fisher
Norma Waterson
Jeannie Robertson
Maggie Peirce
Gill Burns (from Liverpool; is she still around?)
Margaret Barry
Belle Stewart
Heather Wood
June Tabor
Shirley Collins
Anni Fentiman
Helen Schneyer
Maddy Prior
Judy Cook
Jeri

Just a coupla the women who come to mind -- and I like male singers and groups, too! The list goes on...

Bat Goddess