Every day I get a few hits from people using Google to find information on IMEs.  Judging from their search queries, I'm guessing they want to install an IME.  If you are one of these people, try this to start off:
http://www.google.com/search?hl=en&lr=&ie=UTF-8&oe=UTF-8&q=site%3Amicrosoft.com+IME

MUIs (Multilingual User Interace) Packs are extremely awesome.  They REALLY enhance Office.  However for some <adjective> reason, you can't easily get them.  I have them since they're included in my MSDN subscription.  Otherwise, see these links for requirements:
http://www.google.com/search?hl=en&lr=&ie=UTF-8&oe=UTF-8&q=site%3Amicrosoft.com+MUI

Hopefully someday Microsoft will make ONLY English language versions, depending on enhanced MUI packs for localization.