Originally Posted by MUYA
If you want to buy software that already does it, here's what google turned up:
(XML converter 6.00)
(old discussion on conversion methods)
Never used any of these, so buyer beware. From the looks of it though, it shouldn't be too bad to code something up if your needs are simple, and you are willing to dive into and debug parsing word docs (didn't see a real spec in a quick search, so may require some trial and error).