I just learned about a new internet radio network by homeschoolers and for homeschoolers. The Ultimate Homeschool Radio Network currently has about a dozen homeschool speakers giving podcasts on a variety of topics. The shows include:
Some of the podcasts are live, but all can be listened to on the website or downloaded to a podcast player (like an iPod or the Downcast app on your iPhone) or listened to via iTunes.
If you sign up for their email list on the website, The Ultimate Homeschool Radio Network will send you a weekly email of the shows airing that week.