Originally Posted by Amroth
Small Stakes Holdem By Ed Miller, David Slansky and Mason Malmuth is a must.
Im reading it atm and its pretty helpfull
This +1000. Aside from the fact that it will teach you how to play limit holdem well it has a great section in the front where Miller gives a great explanation of how EV works, and essentially what the nature of successful gambling is. Its a fine book.
One thing though. You seem to be wanting to learn limit just to be more well rounded. At the level most of us are at (including you I suspect) you would be better off specializing in one game/format that you enjoy and play well. Getting really good at say 6 max NLHE will be more profitable than being "average" at 4 different games. Don't sacrifice depth of understanding for variety of game play IMO.