While not specifically geared towards smoking and grilling game, Afield: A Chef's Guide to Preparing and Cooking Wild Game and Fish is a fantastic book that covers a myriad of game preparation, from hoof to table. One of its strongest aspects is the way the book reads like a book as much as it reads like a cookbook. It can also take a hunter to the next level when handling his game. Many hunters, myself included, know that they could be more creative and self-sufficient in what they do with our game. This book can push the idea into a reality.
I also recommend Peace Love and BBQ (only one mentioned I own).
In addition, Open Range: Steaks, Chops, and More from Big Sky Country. While not specifically tailored for grilling, most recipes are easily adapted to cooking outside. There is a chapter for wild game, with recipes for venison, bison, fowl, and elk
Something along the line of what Flash Point posted is more of what I'm looking for. More wild game specific. All the other books are great, I've read most of them.