The definitive book on the Iraq War hasn't been written yet. In the meantime, there are two books that I've read recently that describe the invasion in great detail; Boots on The Ground by Karl Zinsmeister and The March Up by Bing West and General Ray Smith. I've written a review of these two books in the following paragraphs.
Boots on The Ground is written from the perspective of the 82nd Airborne. It follows the unit from Kuwait to Baghdad. Throughout the book the author gives us brief snapshots of the various men he observes in combat situations. The vignettes of the soldiers are interspersed with commentary by the author on topics related to the invasion. He lays out a case for going to war, criticizes it's oponents and laments how the press has missed a lot of the more positive stories. All good stuff, but he's preaching to the converted here and I'd rather read about the soldiers. The book is 213 pages long with pretty big print.
My main complaint about Boots on The Ground is that it's way too short. Many of the soldier's stories I've read elsewhere, so much of the material isn't new to me. It's a good book, but I would've preferred to see more material about the actual combat and less political analysis.
The March Up follows the Marine Expeditionary Force (MEF) of the 1st Marine Division from Kuwait to Baghdad. The authors have a great advantage over the other embedded reporters since they are former Marines. One of them, Ray Smith, is a retired general. As a result, the Marines they are with seem to trust them to a far greater degree. They have a front row seat as the division marches toward Baghdad.
At 289 pages and with smaller print this book is much longer than Boots on The Ground. The authors do a good job getting us inside the heads of the Marines and showing us the confusion and struggles of being in a battle. At times, Boots on The Ground and other similar accounts I've read tend to mythologize the soldiers, but The March Up presents their heroism along with their faults. There is very little political analysis which made the book easier to enjoy.
Both books make for enjoyable reading. If you don't know a lot about soldiers or the political analysis leading up to the war, then Boots on The Ground gives you a good start. The March Up gives you an account from a much smaller perspective and is better at showing the everyday lives of the marines involved inthe conflict. Until the definitive book on the entire Iraq War is written, these two should keep you satisfied.