What are the best non-internet reference sources for baseball?
If you had to pick one book, “Total Baseball”. It’s the Official Encyclopedia of Baseball. Besides the complete statistical record of every major league team and player, it also contains chapters on nearly every subject relating to baseball. It’s like a complete baseball library in one volume. For annual information, the annual Sporting News Guide has major and minor league stats, transactions, and day-by-day results from the previous season. Both Baseball America and Baseball Weekly publish annual guides that are pretty good. Dan Nichols has put together a nice page that covers some of the best book on more specific baseball topics.