And then Ankits modified version of the data base....it fixes some of the issues with the original Lahman....
I also would recommend looking into the ERA Calculator and some of the historic .dat files...I believe (but could be wrong) the link is Soxwin's signature, sorry if wrong person...I still have them...I can email them to you if you wanted them and can't find them anywhere...
And depending on if you are going to play the games out...Henry has some very nice historic stadium images to go with the appropiate stadiums on his site
www.bigcitybaseball.com
Thats all I can think of off the top of my head....its been a bit since I ran a historic sim...