The Dark by Lemony Snicket, illustrated by Jon Klassen. Ive looked at this as Jon Klassen is a favourite children's book illustrator of mine, his work is child friendly but quite sophisticated in the overall look of the work he creates. In reference to the theme of my book being Pandoras Box, this book uses dark and light and the idea of fear in a child friendly way.
Mike Mignola's Hellboy. One of my all-time favorite comics, due just as much to the beautiful inking and attention to detail as the strong emphasis on folklore and myths (the Baba Yaga, Irish fairies, etc.), not to mention the smart and believable writing. Whether you are a comics aficionado or not, Hellboy is certain to entertain.