I have not yet listened to Another Frightening Show About the Economy from This American Life. Since it is from the guys that brought us The Giant Pool of Money (the excellent show about the housing crisis), I have very high hopes. Give it a listen if you want to learn about the credit market freeze.
Update: They did another excellent job on this one. What are credit default swaps? What is the commercial paper market? Why do these things matter to me? Why did the market freak out? What does the future hold?