For what it's worth, here's my suggestions on making new formats available.
Since you say you have the source file in .doc format, I will assume you have MS Word. Download the Microsoft Reader Read in Add-in to create .lit files for MS Reader. You can get it from the following page at Microsoft's web site:
http://www.microsoft.com/reader/deve...loads/rmr.aspx
This add-in creates a button on Words tool bar. Just click the button and follow the instructions.
I would then suggest you download a great program called Calibre from:
http://calibre.kovidgoyal.net/
Calibre will allow you to take the .lit file and create .epub, .mobi, and .lrf files.
With these 4 new file types, along with your html and txt files, you have most of your bases covered.
Good luck.