http://discussion.autodesk.com/forums/thread.jspa?messageID=6232057៹
The thread above has a very long discussion, and apparently the files were available directly from Autodesk Support, rather than your reseller (although some resellers may have gotten the files from Autodesk Support and then forwarded them to their clients).
http://discussion.autodesk.com/thread.jspa?threadID=553068
This very long thread has a post from Jeff Agla (May 4, 2007 - way down in the thread) mentioning that files could be obtained from Autodesk Support. I do not know whether they still make these files available, given that the 2009 and 2010 releases support installation on 64-bit operating systems.
David Koch
AutoCAD Architecture and Revit User
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