When you're alone and editing your work, hearing the words come back to you helps. There's an excellent and free online AT&T service that offers voice recognition software at NaturalReaders.Com. (Technically, this stuff is called "text to speech" software.) The free version offers a male voice that is rather electronic, but if you don't mind 2001's HAL reading your work back to you, then you'll be fine. For those who prefer a more human feel, both male and female readers are offered (there is a selection) for a cost: the Professional option is $39.95 while the Enterprise version is $79.50. Each option has lots of bells and whistles (MP3 converter, etc.) if you're interested in that sort of thing.
Personally, I'm happy with HAL. Remember? "Hello, Dave ...."