Elvis Costello & the Imposters will perform an exlusive webcast May 14 following a taped performance on The Late Show with David Letterman,/i>. Broadcasting from the Ed Sullivan Theater, the set-list will comprise songs from The Best of Elvis Costello: The First 10 Years and Rock and Roll Music. This year marks the 30th anniversary of Costello’s debut album, My Aim is True.http://www.cbs.com/latenight/lateshow/live/elviscostello.php