I think PHP is perfect for everybody. These and other forums are available to help you if you get stuck, plus viruses don't seem to come after you as much.
Cost effectiveness goes without saying, and if you're up for/cool with open source, then you should be set.
There are lots of tutorials to help you install php and mysql. Articles here are good, though not many new ones. There are also articles that I've read on Webmonkey, Zend.com, php.net.
At the very least, you can get through installing it and see what you can do with it. You should be able to do a simple phone directory quite speedily.