[MrWorkrate]

For the current season, I love the Baseball Prospectus. It's more geared towards a statistical point of view, offering projections of players from single A to the majors. I wrote a review of it for Amazon.

As for a historical reference, another fun book to check out is the New Bill James Historical Baseball Abstract. It just came out in softcover (it was like a $50 book otherwise), and it offers a cool amount of insight into the great players of baseball history. It goes over each decade, and ranks players alltime by position. James is an aquired taste, and I've heard some people swear by it, and some not like him at all.

As for an every player stat encyclopedia, you can't go wrong with Total Baseball. HUGE book, way too much information, one of those books that you don't necessarily sit down and read, but you keep around just in case you need to look up anything at all.

And, like ctorg said, the best thing you can do is go to a local bookstore (ok, a local "bigger" bookstore, like Borders or B&N) and check out the books before you buy them. Books are written differently, and I've seen way too many that were written awkward and seemed good, but just didn't work for me.