While Call Recorder works great at getting both sides of the conversation into separate, editable tracks it isn't immediately obvious how you can control the audio level of your guest's conversation so that your recording isn't too loud or too quiet.
Ecamm, makers of other awesome apps like Call Recorder, have announced a new app that allows you to stream video from your Mac to Facebook.
I firmly believe if you're going to make something a serious hobby, you shouldn't feel bad or afraid to put some money into it. But you definitely don't have to - particularly if you're short on cash.
Answering a follow-up question to my post for Tools, Gear and Hardware for a First Time Podcaster.