I am not a huge baseball book fan but I do recommend Under the March Sun. it is a neat book about the history of spring training.
Lots of interesting background historical detail.
If you like baseball it is a really good read. While I am on baseball I may as well finish off the baseball books I believe are worth reading. These are in no particular order. All are interesting and well written.
Joe DiMaggio: The Hero’s Life by Richard Ben Cramer
Mickey Rawlings mystery series by Troy Soos (historical fiction)
Tris Speaker: The Rough-and-Tumble Life of a Baseball Legend by Timothy M. Gay
I Had a Hammer: The Hank Aaron Story by Hank Aaron and Lonnie Wheeler