This email from Baseball Reference dropped into my inbox today:
Baseball-Reference.com now has minor league stats from 1992-2007. In
addition to player, team, league and major league affiliate pages, we
also have sortable batter and pitcher leaderboards for every league,
level and year.
You can access it at B-R’s minor league section,
In true Baseball Reference fashion, the database is well organized. It’s sorted by Organization, level and leagues. Of course, everything is interactive allowing you to click away to your heart’s content.