Sadly, Scott fails my podcaster test (Google fails to turn up his name in relation to podcasting), but in this case that's OK. I only get mad at people who apparently haven't produced a podcast trying to teach the rest of the world when they're obviously just linking to high priced stuff to make a buck. Not the case here.
The rule of thumb is to use a microphone of better quality than those typically built in to a laptop computer. Headsets with microphones on flexible booms can be inexpensive and comfortable to use, though they range in quality. Microphones used for public speaking, singing, and voice recording range in price from just a few dollars to hundreds of dollars, but neither price nor technical specifications tell the whole story.
As a starting point, select a microphone at the lower end of your budget and then expect to buy a better one later. Experience using and listening to the results will help you identify any shortcomings. Then again, you may find that your low-end purchase delivers exactly what you need.
This article is one in a series. Take a look.