The Book of Lost Things

This sounds pretty cool, and the cover is sufficiently whimsical without going overboard:

High in his attic bedroom, twelve-year-old David mourns the death of his mother. He is angry and alone, with only the books on his shelf for company. But those books have begun to whisper to him in the darkness, and as he takes refuge in his imagination, he finds that reality and fantasy have begun to meld.