This place is amazing and so simple to use. It's the Education Podcast Network and they've put together in one place hundreds of podcasts from across the disciplines. Music, Science, Language Arts, Mathematics, Health, Social Studies and many more!
Here's what they say: "The Education Podcast Network is an effort to bring together into one place, the wide range of podcast programming that may be helpful to teachers looking for content to teach with and about, and to explore issues of teaching and learning in the 21st century. "
Check it out by going to: epnweb.org. You won't regret it if you do, but you will if you don't!