Is there a way to obtain the names of the top 500 finishers in the Putnam Exam for the years 1991 to 2010?

I'm interested in finding out how students at the smaller universities in Illinois have performed in the William Lowell Putnam Mathematical Competition over the last 20 or so years. I know that the lists of the top 50 or so finishers are readily available all over the place, but the students from the smaller schools rarely reach honorable mention (or higher). I'm particularly curious about the people who scored in the lower places. It doesn't appear that those names are typically published. Any leads on this would be greatly appreciated.