I upgraded my MI install from V2.0 2005.1 to V3.1 3001 recently, and had a hard time finding the required software packages.
If anyone is also looking to upgrade, heres the links on which i managed to find the installers :
MagicInfo Player 3.1
http://yun.baidu.com/share/link?uk=1125378495&shareid=3174759420&third=0&adapt=pc&fr=ftw
(The site hosting this download is chinese, but the installer is in English and virus free!.)
MagicInfo Server 3.1 + MagicInfo Player 3.1
http://shex.pp.fi/magicinfo/
Enjoy. (or not, if you're familiar with the MI software
)