When you open up a document in Outlook or Outlook express it saves the file to a temporary file location. The chances are you saved back to this temporary file, and all you need to do is located the file. Doing a search for "*.doc" will turn up every word document you have on your system. That might be a little bit of a pain to sort through, so try this first bit you can always fall back on the "*.doc" search if you need to. Go to Start and then click run, past this into the run comand box, "C:\Documents and Settings\{YOUR USER NAME}\Local Settings\Temporary Internet Files\OLK241". To find your user name go to Start, My Computer, Local C Drive, Documents and Settings, and there should be a few folders there, the one with your exact user name should be obvious to you and that is what goes in as your user name. A window will then appear with all the word documents you have opened with outlook express and then find the one you saved the changes to and open it and save it to somewhere else more accessable i.e. My Documents.
Let us know if this helps. Have a great holidays.