accessible epub

So, I have a book I was writing and I used Pages to format it. Then I
generated the Epub naively expecting Pages would do a reasonable job of
making the epub accessible. But it didn't, and I do not have the extra time
to fix it (it's a side project, I really do not have the month that it
would take to fix the awful XHTML that Pages generates, in fact whenever I
look at the markup I think it would be easier to rewrite it all by hand, or
even create my own framework)

It would be easier for me to provide a screen reader only version of the
document, that is to say unformatted since it is the formatting that mainly
has created the problems. Does anyone have any suggestions for this -
especially regarding platform discoverability - can it just be that I
specify in metadata for one that it is an accessible version and the other
one that it is not accessible?

Thanks,
Bryan Rasmussen