I wanted to share a podcast that I found on ITunes for salesforce.com 401 and 501 developer exam.
If you click on this it should open up your ITunes and get you to the location.
If you do not have ITunes then I can download the Episode and post them up...
In ITunes the direction is as is:
Podcasts ==> Video Podcasts ==> Software How-To ==> salesforce.com Training and Certification
I hope this helps...