Most multimedia systems sold today allow you to record audio directly to the hard drive with a microphone. Although I could have used a microphone for the Sky piece, I opted to record the artist with my digital video camera (Sony TRV9 about $1,300, although cheaper models can be found ”just make sure they have Firewire ports) plugged into the Firewire port.
Let's talk about Firewire. I have to recommend it for video capture. It allows you to capture clean full-screen video on your desktop, with relatively small file sizes. The quality is much better than comparably priced JPEG capture cards, and the playback (you actually view playback on your camera, which remains connected to your computer) is in real time.
All Mac G3s and G4s come with Firewire capture cards stock; for PCs, the cards usually sell for under $500, and for that price they are usually bundled with a full copy of Adobe Premiere. I shop at http://www.videoguys.com and have been satisfied with their service. So if you are thinking of working video into your Flash work, check out Firewire. (To stay up to date with the growing world of DV and Firewire, get a subscription to my favorite mag of the moment, Res.Subscribe at http://www.resmag.com.)