What kind of microphone hook-up are you looking for, USB or XML? If you’re new to internet radio or podcasting, I recommend sticking with a USB microphone. USB mics are extremely easy to get started on your computer, with little or no software required. They are also a good choice if you have limited space. I use a Yeti mic and it does a nice job.
Should you buy a dynamics or condenser microphone? Some consider this a preference decision. Dynamic microphones typically provide a more vibrant sound with a more casual feel, and condenser microphones are usually more clear but can pick up ambient noise as well. If you don't have a soundproof studio, you may hear hums, cars passing etc.