Because of my husband's work, I had access to professional sound equipment: A Marantz PMD 660 Solid State Digital Recorder, (another professional option is an M-audio recorder), a dynamic microphone, Electro-Voice 635A, and a cable to connect the microphone to the computer.
One of the podcasters at NetSquared, where I work, uses the Olympus DM-20 digital recorder, which isn't cheap, but is more affordable than the options above, and I think it comes with a microphone.
After I did the interview, I was able to connect the recorder to the computer via USB and download the interview (which I recorded as an MP3 at 44.1K) into my iTunes. I edited the interview in GarageBand and exported it back into my iTunes. I converted the file back into an mp3 in iTunes (Garageband exports it as an AIFF file into iTunes) and uploaded it to Gcast. I chose Gcast because you can easily embed your podcast into your blog or webpage. This seemed like the most accessible option. I know that many people don't know how to subscribe using RSS feeds and/or don't have an mp3 player.
Audacity is another free software option you can use to edit podcasts.
When I wrote a similar post to this one on on Blogher, a reader wisely commented:
That's an awful lot of audio transcoding going on (at the very least, MP3 to uncompressed for editing, back to MP3) which will introduce a loss of quality. Since you're using the PMD 660, why not record uncompressed (as WAV, for example) and edit that? Then there's less transcoding going on.The final step that I need to do is to register it with podcast directories like Yahoo, Podcast Alley and Podcast.net. Gcast automatically submits it to the iTunes Music store.
Remember, MP3 is lost compression - when you uncompress (for editing) you lose stuff.
I hope that helps aspiring podcasters. If I can do it, you can too!