I stumbled upon your thread today and believe me, I feel your pain! I've been converting all kinds of documents for over 4 years now and getting a Word doc to EPUB is just a painful process.
What we found works best is to first convert it to PDF, then convert the PDF to HTML and then to EPUB. Converting to PDF first gets rid of all that junk Word outputs and gives you a better baseline to work with.
We've actually developed a web-based application (
www.rocketdocs.com) that's based on this very process and it works flawlessly. No HTML or CSS coding involved.
Hope that helps!