If you provide multiple podcast shows to iTunes audiences iTunes can help you manage them all in one place.
From Apple's Podcasting FAQ: http://www.apple.com/itunes/podcasts/creatorfaq.html
How can I create a page that aggregates my podcasts?
If you have multiple podcasts listed in the iTunes Store, the iTunes staff can create a single page that lists all of them in one place. They call that page a “provider page.” Note that a podcast can only appear on one provider page.
To request a provider page, navigate to one of your podcasts, click Report a Concern, and select Remove a Podcast. In the dialog, explain that you would like a provider page, give us the exact name of the provider (please don’t include “Inc.,” “LLC,” and so on), and list the iTunes Store links to your podcasts.
