I went by Borders and Barnes and Noble, asking about book donations in regards to Katrina.  Borders doesn't have anything going on right now, but they usually have something like that going on around Christmas.
Barnes and Noble does have something they call Feeding the Children, but will accept pretty much any sort of book, and they said that they'd make sure they would get the books to people in areas affected by Katrina.  They said if we wanted to do something regarding OU, to let either Kent or Susan there know (they're managers at Barnes and Noble).
Hope that info helps.