i know several blind people who have one or another of the flavors of the
Creative labs muvo.  The bottom of the line unit, which has 128 MB of
storage, has no display, and only a few controls which are easily learned
by a blind person.  in fact, AUDIBLE.COM offers this one for free if you
sign up to receive their content.  There are other models that offer
storage up to 4 GB and offer other features, such as an FM radio receiver
and digital voice recorder.  These have an LCD display, and may be more
difficult for a blind person to use, but i have a friend who has the 512 MB
model, and uses it daily, mostly to listen to his collection of music in
MP3 format.  They work like a USB thumb drive, in that you plug it into a
USB port on your PC and it is recognized as a drive under Windows Explorer,
and you can just swap files between it and your PC just like you would do
with any other drive.

Andy