For my podcast I use Audacity to record, I use a cheap headset microphone that was $20 at Staples. Its an Altec Lansing. The Logitech that I had before was decent but it broke two weeks after. Not sure if it was my fault or the headset, I tend to say it was the headsets fault, lol.
If you are looking to record a group of people. I know a group of drag queens who do their show with one of those $20 microphones that you can pick up at Wal-Mart and they sound really good.
Here are a couple of other programs, I have them installed but have not had time to test them out. Both look promising. Adam Curry uses CastBlaster.
CastBlaster (free Beta)
Always hear about how great GarageBand is for podcasting, but not having a mac myself, what are the options for good (not exhorbitantly expensive) podcasting software and any good mics? I heard a podcast that was recorded on some USB condensor mic and that sounded pretty good