Never read Graham Joyce--what genres does he write?--but The Green Mile is definitely on my top ten (which is really my top twenty or thirty--there are a lot of ties). That said, I think every writer should read (pardon me if this has already been mentioned) Stephen King's On Writing. It is an interesting mix of memoir and instruction.
It's difficult to define Graham Joyce's books. Even he scratches his head when you ask him that. He is most certainly not magical realism, nor is he horror. If I say 'Dark urban fantasy', that probably points you in the right direction. The Tooth Fairy is just extraordinary. It's about three lads and a girl growing up in the Midlands (England, not the US) in the 1970s. One of the lads, Sam, 'sees' the tooth fairy, a sometimes malevolent, sometimes friendly creature. I guess it could be summarised as a rites of passage novel. But that doesn't do it justice, really; there is so much going on its impossible to say more without writing a whole novella! If you can get your hands on a copy I do recommend it.
King's 'On Writing' is a fabulous book, and one of the rare instances when I became immersed in an audio book. He reads it himself, and listening to King telling you about his life and the Craft, through a pair of iPod earbuds, is an intimate experience I recommend to everyone. I'm told his readings on earlier books were very poor, but by the time he read 'On Writing' he'd mastered the art of narration.
Back to the original topic, the book to read before you die is A Game of Thrones by George R R Martin, and spare some time to fit in the rest of the series.
Now, the real trick is getting him to finish writing the series before he dies...
I'm not a big fan of fantasy, Joel, but you're quite right, A Game of Thrones is an amazing book. I'm halfway through a A Clash of Kings as I write this. Epic! Yet it's all about individuals. You never get the feeling that the myriad characters are mere pawns to be shuffled around as the plot develops. Some writers lose that touch when the book/series gets too big. Reading GRRM is a humbling experience for a writer. No one will match GRRM's achievement for a long long time. Let's hope he doesn't go the way of Jordan and Brooks and Eddings and Goodkind, churning out pointless sequels that advance the arc not a jot.