BradyGames posted a PDF sample chapter of the achievements book I co-wrote late last year. The sample chapter contains the full Achievement Guide for BioShock, which was one of the eight I wrote. The book contains Achievement Guides for twenty games as well as a "How to Score 10,000 Gamerpoints in Two Weeks" chapter that I put together for those looking to get their Gamerscore up as fast as possible.
Click here for the sample chapter.
It's a "pocket guide" at 4x8.5" in dimensions and 320 pages, but it's got a ton of info in it. If you haven't seen it or won one in my giveaway last month, I definitely recommend picking one up. And no, I don't work on commission.