Repair permissions and then search for a file called Normal. I have Office X and my Normal file (the Word template) is within a folder in my Microsoft Office X folder (in Applications) called Templates. Select this file and then select Get Info from the File menu. In the Ownership & Permissions section, does it say you can Read & Write?
We are having the same issue it is with Adobe files too. Also we are only having the problem on our 3 machines that have Snow Leopard. Any help would be great as we are getting hammered form employees that are ticked.