 The Harry Potter books put readers under a spell in the 90s, and they are still breaking records to this day. A watercolor painting of the first edition of 1997's Harry Potter and the Philosopher's Stone sold for a record $1.9 million. That makes it the most expensive piece of Harry Potter paraphernalia ever sold. If the image looks familiar, it's because a different title and cover were used on books in the U.S.,