I would definitely get a dv camera, so that you can bring your footage back to the computer via firewire or the 1394 connection on your computer, that allows you to keep the highest quality for your slow motion analysis. Also make sure the camera that you pick has some basic options. Most cameras have a sports setting you can choose which uses a higher shutter speed, allowing you more frames for your swing analysis. In working with our school teams we use an inexpensive Panasonic, I think it was 289$ and have great results, We also use the home v1 software
http://www.ifrontiers.com/consumer/default.asp which works great and is relatively inexpensive.
hope that helps. Curt