I show how I approach recording a podcast that has two hosts remote to each other and a sound effects track going "live to hard drive". We still end up with multiple tracks (three) for the ability to enhance each track as needed without modifying the others. I demonstrate the easy trick to lining the tracks back up in sync before editing.

We use Audio Hijack Pro, Soundboard and Mpeg Streamclip in our example.
http://rogueamoeba.com/audiohijackpro/ - $32 USD
http://www.ambrosiasw.com/utilities/soundboard/ - $29 USD
http://www.squared5.com/ - Free