Here's The Bar Book: Elements of Cocktail Techniques, by Jeffrey Morgenthaler, bar manager at Clyde Common in Portland. As the title suggests, the book is arranged by technique, but it might be more accurate to say The Bar Book explains why cocktails contain certain elements. Why would you add soda to some cocktails and not others? Why does the size and shape of the ice matter? Why do you shake cocktails? Stir them? Muddle? Why would you set something on fire?
This is not a book for the recipe hound, someone looking for 101 things to do with spiced rum or creme de menthe or whatever other bottle of liquor is burning a hole in your bar cabinet. There are recipes, yes, but they are illustrative of techniques. Rather, this is a book for people who know the basics, know the classics, and want to improve their cocktail game from good to great.
Warning: this book may lead to hours of bidding on eBay for vintage bar tools.