When I was little I remember reading a book that wasn't an official Choose Your Own Adventure kind of thing (IIRC), but was written in that style. It had a fantasy setting, and you were looking for a ring that belonged to an evil wizard. The actual nature of the ring was different depending on what ending you got. Sometimes it was a literal ring, sometimes it was a kind of wood called "ringwood" or something like that, and sometimes it was the ring around a planet. There was also a girl with auburn hair, they mention the "auburn" bit a lot. I thought the title was "The Ring of Meader" or "The Ring of Meever" or something like that, but Google is failing me. Does anybody remember the book?