If you don't know about them, check out the Ashbrook Podcasts. Because I teach World History this year, I am always jonesing for a little more American history. I have downloaded most of the Teaching American History podcasts and they are all great. My personal favorite is the Robert Ferrell on Calvin Coolidge (of course). Highly recommended for anyone teaching American history. You will learn something (I do/did).
Don't neglect Schramm's "You Americans." He has featured "our favorite journalist" Tom Suddes a couple of times. They are always interesting as well. For those of you who have iTunes, follow the link to the Ashbrook Podcast page. Copy the link to subscribe. Then open iTunes, under "advanced" select "subscribe to podcast" and paste the link. Easy as pie.