One interview was conducted on the NPR radio programme "All Things Considered:" http://www.npr.org/templates/story/story.php?storyId=98081089 (8:20)
Elliott Carter discussing his new piece, Caténaires, for pianist Pierre-Laurent Aimard and the Ensemble Contemporaine (26 October interview from New York): http://www.youtube.com/watch?v=bp95zFUPEj0&feature=related (9:58)
He was also interviewed on NPR (National Public Radio, US) on the Charlie Rose Show (PBS) alongside pianist/conductors James Levine and Daniel Barenboim. The Youtube clip is an excerpt from the interview and contains Barenboim's recollections of his late friend, Edward Said, and his reminiscenses on the 'late style.'
http://www.youtube.com/watch?v=qiDd4JVN9Vo Alternatively, one can watch the entire interview at http://www.charlierose.com/
Other recent interviews include one with Frank Oteri (American Music Center - New Music Box) from mid-2008: http://www.youtube.com/watch?v=Zzs8Ov2p-Rc (5:08)
Also in celebration of Carter's 100th birthday, the Library of Congress has digitised the manuscript sketches of his Sonata for Cello and Piano and the String Quartet no. 1. http://lcweb2.loc.gov/diglib/ihas/loc.natlib.ihas.200155900/default.html Lastly, they have put up a digitised version of The Musical Languages of Elliott Carter (1984) by Charles Rosen which operates in a manner similar to the British Library 'Turning the Page'.