Kingbird Highway by Kenn Kaufman is absolutely essentially and was my birding bible growing up. :) Also To See Every Bird on Earth is a good novel, as is Life List. And if you're looking for more of a "classic," Roger Tory Peterson's Wild America is incredible. It's also helpful to start reading different birding blogs such as 10,000 Birds or Cornell's Round Robin to stay up to date on latest findings and news in the birding world. There's a ton of stuff out there, so it's mostly a matter of finding what you like. Good luck and have fun!