Doyle Brunson's Super/System 2
Doyle Brunson (and friends) update the Poker Bible (Super/System I) Written by Jesse McLean
The original Super/System is widely referred to by poker players as "the Bible". They're not really joking either. It covered all the major poker games with chapters written by the best players of the era. Super System Two (SS2) is also a collection of big name players writing about one game each. It was eagerly anticipated by pretty much every serious poker player.
People are not quite sure whether SS2 is a replacement for SS1, a compainion volume, or just an updated edition. I would say it definately works as a stand alone book, but large parts of the original Super System cover concepts (and even entire games) not covered in SS2. If you're only going to get one, get SS2, but if you can find a package deal, or a cheap copy, the original is well worth its price as well.
Article continued on: Best Poker Offers
David Sklansky's Theory of Poker
Sklansky's Theory of Poker is not an easy read, but it is one the fundamental books of modern poker
Lee Jones' Winning Low Limit Holdem
Jesus doesn't want you to read this book!
DD Tournament Poker
DD Tournament Poker is a good way of practising for multitable tournaments.
Ed Miller's Small Stakes Holdem
This book is the graduate course in beating low limit games.
David Sklansky's Holdem for Advanced Players
Holdem for Advanced players by David Sklansky is one of the most important books about the game.