Here’s a great one from one of the gurus of great web design, Paul Boag. Productivity Tips
I have been a follower of Mr. Boag’s for years now, a regular listener to his podcast, and his insight has opened up a lot of doors for me. Check out his blog at boagworld.com and listen to his recently revamped podcast on iTunes. The podcast is set up in such a way that he divides it up into seasons based on who he is addressing (ie. Season 1 is aimed towards website owners, Season 2 towards the web designer). Regardless of this, there is great usable information for web designers in every podcast.