I thought Stephanie Meyer did a nice job with the idea of the author's note on her website. She discusses the background of shapeshifting mythology in the Quiliute legends that she used for New Moon (you can see it here (http://www.stepheniemeyer.com/nm_thestory.html)). Knowing that she'd drawn on real legends--with the kind of respect you're talking about--gave me a much deeper appreciation for the books than I'd had before.