Skype has run it's own online store for video and voice conferencing for quite some time. Problem was few if any of the webcams they listed were Mac compatible. Recently they updated their online VOIP hardware department with a better selection of Apple friendly web cameras and headsets.

The
FREETALK Everyman HD Webcam
is a 720p capable high-definition cam that can fit the bill for those of you with, say, an Apple Mac mini or Macintosh Pro tower that doesn't come with a built-in iSight web cam like the iMacs and MacBook models do. Unfortunately, this cam doesn't include a built-in microphone - so you'll want an external mic or headset to go with it.
Plug and Play USB 2.0 port is all you need for webcam chat for Skype on the Mac. You might also be interested to know Skype v5 went from beta to official release, so check out the latest version at the
Skype For Mac download section of their website. A redesigned interface tries to simplify things. Personally, I'm sticking with the previous version for the time being.