Get Running Forums

I listen to the Marathon Training Academy podcasts, which are surprisingly good! The two presenters are easy to listen to and there is so much excellent advice in it – like how to deal with blisters (ouch). Also, they talk a lot about the benefits of marathon running so it's very motivational.

http://marathontrainingacademy.com/

I must second Tangerine for creating appropriately paced workout music playlists: http://www.potionfactory.com/tangerine/

Apart from that, audiobooks from time to time if they're exciting ones...