Discovering Podcasts - help?

A discovered that a friend of mine has started making podcasts, which is one of those terms I've been hearing but not paying much attention to it. OK, it's a Phenomenon. I've decided to sample it. Where do I start? Well, ok, I'm starting by downloading my friend's 3 Podcasts onto my ipod shuffle (I had to call her to help me figure out the intuitive Apple interface in I-Tunes, but I finally managed it.) I gather that there are hundreds, thousands, gazillions of podcasts out there. Should I just sample the handful that Apple has decided to feature in their I-Tunes site? Or should I make a point of ignoring all of those, not wanting to be a pawn of the establishment. Anybody got any favorites to recommend?