I couldn't find anything specific about this in the help section.  I received a book that smells pretty musty.  It doesn't bother me but it might bother someone else.  Is it postable?

Any ideas on how to get rid of musty smell?

I think that it is postable. If someone doesnt want a book that smells, they can say so in their requestor conditions.

Try sprinkling the pages with some baking soda & leaving it in a plastic bag for a few days.  If it's just mustiness and not mold, this will sometimes work.