Anyone know of any well-supported/proven methods for converting a Microsoft word document to an MP3 or wav format such that hearing-impaired folks could "listen" to documents that I have stored in my web-based document management system?

I already have the interface built such that someone can use the telephone to get the list of documents available, with the dates and titles "read" to them over the phone, but now I would like the ability to let someone actually listen to the contents of word files stored in the system.

Ideally a .net library or utility that would let me convert the DOC -> MP3 after each upload would be best, but one that "read" the file on demand would be OK too.