Book I read in grade school and wish to read again

[radetlor]

I read a book in the late eighties (in the elementary school library), and I only remember one thing besides that the book freaked me out. It was a book of short stories, and one of the stories had a toothfairy. The illustration was a very mean looking, ugly, wrinkly toothfairy, with a castle made of teeth behind her. I think the name of the book may have something to do with rainbows, or that one of the stories was named "The secret about Rainbows" or something similar. If you can help me out, its driving me crazy for years!

[Rosetta]

I have not read it myself so its only quess work.. Could it be a short story by Edgar Allan Poe. Does that ring any bells. I have tried googling i t but cant see a reference to a story about a toothfairy, but it may well be titled as something else