The Asphalt Jungle, by W.R. Burnett, is generally considered the first modern "heist" book - that is, the first crime story to be told entirely from the point of view of the criminals.
Rosetta Books publish an e-book version.
Ben G also mentioned Eric Ambler's
Light of Day (aka "Topkapi"). This is an excellent novel, but I'm not sure it counts as a heist. It's true that it's set against the background of a major robbery, but it's really the story of the decline in fortunes of a petty criminal who gets sucked into a situation that's above his head. Definitely a good read.
Mike