If you enjoy articles and esseys about baseball, especially related to statistical analysis of baseball, please take a look at Hardball Times.
I've been reading their web site for some time, and they just recently released their annual book. My buddy Dan Fox contributed a couple of articles for the book, so that alone makes it worth it, in my opinion. I've always marvelled at Dan's writings. I'm they type who's always wondering about things, but he actually does the research and formulates an answer. I'm obiously much more lazy.
I'm also currently reading the book, "Mind Game," written by the guys at Baseball Prospectus. I've always enjoyed the BP guys (their annual book is a must have for my Spring Training trips), and this book takes a look at the 2004 Red Sox to analyze what Theo and the bunch did right to bring home the hardware. I'm about halfway through the book and am enjoying it very much. I recommend it.