I know writing excuses covered ePublishing in season 5 episode 28 (By coincidence I had just listened to is) and they covered self-publishing ebooks as part of that.
Also, season 3 episode 21 talked specifically about epublishing. At the time, everyone recommeded against self-publishing if you could help it. But the last 5 years have made a lot of changes in the industry. I'm wondering what their answer would be now.