USB Microphones for Recording Podcasts & Screencasts
Adobe Captivate PM, a popular tool for recording screencasts and e-learning courses, has a round-up of popular microphones for recording podcast narrations:
A friend of mine has been using Blue Snowball USB mic to record the SMEs who think it’s really cool because it has a bit of a retro look. This is an omni-directional mic, meaning, it will record audio from all directions including ambient noise. A quiet or soundproof room will give you best results. You might also want to invest in a Pop-Filter. They are cheap and worth it.
In most cases though, I just use a very simple and cheap unidirectional mic or my Plantronics headset. They do the job in 99% of the projects. Link.