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Whenever this question gets asked I always respond that you will learn as much or more about hunting by reading books about hunters and hunting but that aren't how-to books (they have their place). A book like Stewart Edward White's The Long Rifle was as useful to me as Boyd's Blacktail Trophy Tactics (a good book). That said, here is a list of books, not all strictly hunting related, that have taught me something about hunting:A Sand County Almanac by Aldo LeopoldThe Long Rifle by Stewart Edward WhiteBlacktail Trophy Tactics by Boyd IversonTrophy Blacktails by Scott HaugenThe Big Sky by A.B. GuthrieMountain Man by Vardis FisherThe Complete Guide to Hunting, Butchering and Cooking Wild Game Volumes I & II by Steven Rinella A Year in the Maine Woods by Bernd HeinrichIndian Creek Chronicles by Pete FrommElk of North America, Ecology and Management Jack Ward Thomasjust to name a few...