Almost any book will give at least a small perspective that will add chips to your intellectual stack. Gordan's "Little Green Book" is the one I recommend for beginners to Hold'em but I reread it every couple of years because it has solid principals and is an easy read. The autobiographies like Green's "Ace on the River" impart the hard learned lessons of the professionals which, if taken to heart, may save you a lot of bad decisions made outside of the games such as not chasing, walking away from a game that doesn't have sufficient
equity, learning to gain perspective on bad beats. I like specializing to begin with, say NL Hold'em tournament play books like "The Raiser's Edge" mentioned above or Harrington's books. Then start adding variations: cash games, limit games, brick-and-mortar vs. online,etc. then pick up Omaha, Razz, stud, and so on.