Test Driven Development and xUnit seem to be popular among many of the professional and very public programmers, so I thought I might like to give it a whirl and see if I can improve the flexibility of my source code and better decouple objects. Unfortunately, I use WAMPServer on Windows as a development server while at work so directions for installing PHP related plugins/PEAR aren't exactly identical. (Usually, I can figure it out fairly quickly.)
His installation technique involved having the PEAR tools installed so you can just pull it from the PHPUnit channel. Then all you'll need to do discover the PHPUnit channel and call the "install" and let it do the rest of the work. For those wondering, this is pretty similar to the installation process on a unix-based system, just without the Windows-specific script calls.