ORIGINAL: Nikademus
For a quick (one book) read i'd third the suggestion for Costello's "The Pacific War"
IMO its one of the more under-rated books of the Pacific, mainly because nitpickers like to chortle over minor editorial errors, mainly to due with ship name spelling or a transposing error or two. These small errors mean nothing though for a book on the scale of covering the entire war. IMO, the best and most facinating part was his preface section to the war itself which goes into the history, politics and economics behind Japan and the US's stormy post WWI relationship. It does much to dispell the white hat/black hat simplification one tends to get and allows the reader to begin to understand the complicated dynamics between two powers, their differing goals and viewpoints etc. (Judging of morality is left to the reader as it should be)
The 2nd best part of the book is that it covers the less well known aspects of the PacWar, such as the CBI and China theaters, including their politics and such. Its a good all around read for someone who wants a good primer for the war in one volume.
Definitely Costello's book.
Also, for free check out the HyperWar website. A number of official histories are there, some still excellent after over 50 years.
For pre-war I would read Kaigun (Peattie and Evans) and Sunburst (Peattie), both about the development of the IJN.
Also, another free book that has an interesting twist about pre-war tensions: To Have and Have Not: Southeast Asian Raw Materials and the Origins of the Pacific War available at
http://www.escholarship.org/editions/vi ... nd=ucpress
Also, Edward Miller's two books: "Bankrupting the Enemy" and "War Plan Orange"
And Lundstrom's "Black-Shoe Carrier Admiral" on the first 11 months of US Navy carrier operations where the under-rated/over-criticized Frank Jack Fletcher was mostly in command.