Podcast
Chicago Manual 14.267
See examples below:
Notes-Bibliography Style
       1st Footnote or Endnote
           2. Michael Shear, host, “The Spat over President Obama's Upcoming Jobs
       Speech,” The Caucus (MP3 podcast), New York Times, September 1, 2011,
       accessed September 6, 2011,http://www.nytimes.com/pages/podcasts/.
       Bibliography
       Usually not cited in bibliography.
Author-Date Style
       1st Parenthetical Note
       (Shear 2011)    
       Reference List
       Shear, Michael, host. "The Spat over President Obama's Upcoming Jobs Speech."  
           The Caucus (MP3 podcast). New York Times, September 1, 2011. Accessed     
           September 6, 2011. http://www.nytimes.com/pages/podcasts.