What's a really good book just about the overall history of baseball? I've tried looking at Barnes and Noble, but to no avail.

Baseball. It was a documentary by Ken Burns which was awesome and they made a book version also. It is without a doubt the most interesting and informative. Includes the Negro leagues and 1st hand accounts of the early days. If you get a chance, watch the documentary as well. It's long, but worth it.

Try PBS - several years ago someone did a very good series on baseball (same guy who did the Civil War) and I seem to remember that they did a book after the program was aired. I think you can buy the DVD's, but they may well have a book as well.

You can get Sports Illustrated Baseball book or ESPN Baseball Encyclopedia.

Diamonds in the rough : the untold history of baseball
by Joel Zoss; John Stewart Bowman

One of the better single-volume history of baseball is
Charles Alexander's "Our Game".

The classic history of the game is Harold Seymour's 3-volume set:
Baseball: The early years
Baseball: The golden years
Baseball: The People's game

The first two volumes focus on the early history of the game and the evolution into professional/major league status. The third volume focuses on baseball at other levels - college, semi-pro, mill leagues, etc....

All of these should be available through Amazon.

Ken Burn's baseball is the best thing i've seen.