Start with the Comic Book podcast wiki and

ADD:

Doctor Who: Panel to Panel
The Comic Show
X-Ban: The Phantom podcast
Women of Marvel podcast
WeBeGeeks: Mighty Marvel Geeks
The Elfquest Show
Longbox Heroes
Crooked Comic Cast
DC Comics Presents Show
The Joe Schmo Comic Show
League of Ordinary Gentleman Comic Book podcast
We've Got Issues
Four J's and a Comic
Graphic Novice
Comic Book Central
Film Dispenser's: Loose Staples
The Comics Dash podcast
All About X-men
Geekcast Radio:The Pull Bag
Ultimate Spin
The Mass Comic Unboxing
Ultimate Spin
Comics and History
The Culture of My People: The Monthly Issue
Comic Book City
The Hornet's Nest