http://ax.phobos.apple.com.edgesuite...1681b784591cab
Full concerts to download for free from iTunes artists include
Radiohead 2hr gig
Travis 1hr52
Belle and Sebastian 1hr40
Peter Bjorn and John 1hr32
and many more
simply search for npr on the itunes uk site and choose "live concerts from all songs cosidered podcasts"
Hope you find something you like