The Internet Poetry Archive (University of North Carolina Press) has audio files of Wilbur reading. He reads well. Dimensions of the poetry are heightened -- his wit and heart more evident.
The Archive also has other poets reading: Seamus Heaney and Robert Pinsky among my favorites. Includes Pinsky's amazing reading of "Shirt." Having toiled before a sewing machine a few hours myself, this reading gives me shivers.