OOTP 8 and 9 come with the Lahman historical database. This thread is still accurate, even though it's from last year, about importing historical teams into a custom league:
http://www.ootpdevelopments.com/boar...t-seasons.html
Similarly, this thread deals with importing individual historical players:
http://www.ootpdevelopments.com/boar...ar-league.html
Regarding controlling everything, there is a setting in League Setup, Functions, called "Set All Teams To Being Controlled By [your human manager identity]."
It helps to play in Commissioner Mode (Manager Options) to do things like editing players. When you go into that mode, you will notice an Editor tab appears on every Player Profile page.
Finally, accurate player photos/team decals can be found at this web site:
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