Listmania!
These books will make you improve in poker
The Theory of Poker: A Professional Poker Player Teaches You How to Think Like OneThe Theory of Poker: A Professional Poker Player Teaches You How to Think Like One by David Sklansky
Buy new: £11.55 / Used from: £12.99
The book you should definitely buy! It doesn't teach theory of a specific game, but gives you general theorises used for any poker game (slowplaying, odds, position etc)
Harrington on Hold 'em: Strategic Play v. 1: Expert Strategy for No Limit TournamentsHarrington on Hold 'em: Strategic Play v. 1: Expert Strategy for No Limit Tournaments by Dan Harrington
Buy new: £13.14 / Used from: £11.00
The standard of no-limit tournaments, this shows you how to play at the early stages of a tournament, to survive with a stack
Harrington on Hold 'em: Expert Strategy for No Limit Tournaments: The EndgameHarrington on Hold 'em: Expert Strategy for No Limit Tournaments: The Endgame by Dan Harrington
Buy used from: £14.90
And the sequel helps to improve your end-game strategy, ensuring you go deep in the money
Caro's Book of Tells, the Body Language and Psychology of PokerCaro's Book of Tells, the Body Language and Psychology of Poker by Mike Caro
Buy new: £11.96 / Used from: £10.36
The first real book on tells, it's still considered important today. This will help not only to pick up on tells, but determine the certainty of the tell, depending on the skill level of the player.
Phil Hellmuth Presents Read 'em and Reap: A Career FBI Agent's Guide to Decoding Poker TellsPhil Hellmuth Presents Read 'em and Reap: A Career FBI Agent's Guide to Decoding Poker Tells by Joe Navarro
Buy new: £6.72 / Used from: £4.47
The modern book on poker tells, slightly more broad than Caro, but it has some new ideas on poker tells, and would be a great supplement after Caro.
Phil Gordon's Little Green Book: Lessons and Teachings in No Limit Texas Hold'emPhil Gordon's Little Green Book: Lessons and Teachings in No Limit Texas Hold'em by Phil Gordon
Buy new: £8.08 / Used from: £5.50
Phil Gordon's writing is brilliant for the beginning player who understands the basics, and wants to learn to improve. In particular, the writing on how to play different hands is superb.
Phil Gordon's Little Blue Book: More Lessons and Hand Analysis in Texas Hold'emPhil Gordon's Little Blue Book: More Lessons and Hand Analysis in Texas Hold'em by Phil Gordon
Buy new: £8.08 / Used from: £5.30
The sequel to LGB, this book shows hands Phil Gordon has played and the factors he considered to determine the best decision.
Mathematics of Poker, TheMathematics of Poker, The by Bill Chen
Buy new: £12.20 / Used from: £8.75
Chances are it will boggle your brain, but this book is probably the best on the mathematical side of the game
Killer Poker Online: v. 2: Advanced Strategies for Crushing the Internet GameKiller Poker Online: v. 2: Advanced Strategies for Crushing the Internet Game by John Vorhaus
Buy new: £6.30 / Used from: £4.57
I reccomend this, and the rest of the Killer Poker Series on helping you to be successful as an online player.