Strangely, there are also tales of ugly women who are really beautiful (See King Henry (http://www.sacred-texts.com/neu/eng/child/ch032.htm), which I like because it doesn't appear that she's under any kind of spell or enchantment except her own - she just wants to make sure he'd really do anything for her). Also worth noting is Alison Gross (http://www.sacred-texts.com/neu/eng/child/ch035.htm), who responds to rude rejection by turning her beloved into a worm. Steeleye Span leave out the bit where the queen of faerie turns him back again - I prefer their version.