From Sorcha:

"But, hasn't Tam Lin been done to death?"

I don't know... has it been done as an illustrated children's book?

One related ballad which is related to Tam Lin is "True Thomas" -- a bard /poet being taken into the realm of the faery for seven years and gaining the gift (or curse) of prophecy... and he was an historical person.

I know his story has been retold as a novel. Not sure if it's been done as a children's book.

But my favorite ballad is "The Bonnie Lass of Angelsey" (Child ballad #220), which tells the story of a strong, independent woman. A king, jealous of her wealth, thinks he can "win" it away from her, but she turns the tables on him.

It can be found in the Digital Tradition here.