U2 Album Sale on Amazon.com, Playing Letterman For A Week

U2 – “Get On Your Boots” (Click To View Video) U2‘s new album, No Line on the Horizon, doesn’t come out until March 3, but right now you can download a bunch of their other albums on mp3 on Amazon.com for a mere $5.99 each. Also, in order to launch the new record in grand…