AC/DC will release their entire catalog to iTunes.  The Australian rockers were one of the few bands to hold out from the popular digital music store.  You can download full albums and individual songs.  That includes the band's brand new live album, Live at River Plate.

The BeatlesLed Zeppelin, and Metallica are all bands who also refused to sell their music on the digital music store before finally relenting.  One of the biggest issues that bands like AC/DC have with digital music is that it encourages people to purchase individual songs instead of albums.  Of course, the Australian rockers have released singles throughout their career.