Recording a podcast is, theoretically, a simple affair requiring a microphone and a something to record onto (normally a computer these days). The theory is fine, but in practice it’s a lot harder than it sounds!
I use a variety of different microphones, depending on the situation.
I’m also a big fan of the mics from Blue Mic, I just don’t happen to have one that I actively use right now.
For the moment, I’m doing interviews via Google Hangouts, which, while it has a number of frustrations, is currently the easiest, most universal way that I have to record an interview online. If you have other suggestions, speak up.
Actually plugging in a microphone and starting a recording isn’t hard, but getting the levels correctly setup so that it it’s usable, figuring out what to say and sitting in a room talking to yourself all take a bit of getting used to. It’s certainly not as simple as it looks!
I do all of my audio editing on Audacity . Audacity is free (for all appropriate definitions of free), and very easy to learn and use. I run Audacity on Fedora. Typically, a minute of finished audio that you listen to takes 2 minutes to record, and 3-5 minutes to turn into the final product. (Video takes even longer.)