http://bugs.winehq.org/show_bug.cgi?id=10787
--- Comment #5 from Joseph josephjacir@hotmail.com 2008-01-13 19:06:19 --- http://usa.autodesk.com/adsk/servlet/mform?id=10083915&siteID=123112 This is the official site. Unfortunately you have to sign up. I believe it will also give you the latest version, which is not necessarily always going to be 9.
However, the software is available to download at no charge; it comes with a 30 day trial. Here is another download source I've found which hosts version 9. http://www.soft32.com/download_81704.html