We're big fans of Ira Glass and the This American Life radio show/podcast. We listen to every show on the podcast and there are few broadcast storytellers that I respect more. Via an older post on the Explainist blog, I found these videos of him describing the process of researching and crafting stories from back in 2006. He names two building blocks of storytelling and how they work together. Really great perspectives that you can hear in every story he tells.
The video above is actually part of a 4 part series and the other parts are less applicable to our work, but still worth the time to watch, especially if you're interested in broadcast work like his show. View Part 2, Part 3, Part 4.