If you've got luck and cash, try and book a private tour with MaryAnn Squires, the wife of J.D., who bred Monarchos. She'll get you in anywhere and she knows everyone. The contact info is Kentucky Horse Tours (Mary Ann Squires) (859) 312-1124.
Go to this website for all sorts of horse farm tour info:
http://www.visitlex.com/quick/tours.html
HAVE FUN!