I highly recommend this book, Snowball, by Alice Schroeder, which documents Warren Buffett's life, including both his personal and business life. It is very long, but very worthwhile reading. Buffet is considered by many as the greatest investor of all time.
The book does describe Buffett's investment philosophy. Much can be gained by learning his important lessons of incredible discipline and patience, as well as how he has used past weaknesses in the market or specific companies to buy, yet be patient when others are greedy. However, much of the book discusses Warren's personal life, from his childhood newspaper delivery business (he built an "empire" as a teenager) to his relationship with Bill and Melinda Gates.
The title of the book represents Buffett's investment philosophy, that money invested and allowed to accumulate and compound over many, many years will "snowball" into even more money. He certainly has succeeded at this.
While I recommend this book, a previous book on Buffett by Roger Lowenstein, written in the 1990s, provides more information on the business side of Buffett and his investment decision making.