I was in the same spot you are not too long ago. ASP and HTML background, but no real experience with PHP or MySQL. Fortunately, PHP and MySQL are pretty easy to get started with, and a lot of the stuff you've learned for ASP can be put to work in PHP. Here's tutorial that helped me a lot: [devshed.com...]
This tutorial deals with managing press releases, but it shouldn't take too much effort to convert this to manage names and coresponding phone numbers.
Also, even though PHP and MySQL typically run under linux, they both work like a champ in Windows as well. If you want a development/test environment for PHP and MySQL, you may want to look into a Windows installation kit for Apache/PHP/MySQL/Perl. Some popular ones are Firepages, FoxServ and PHPTriad. I've used all three. They are very easy to set up and don't seem to interfere with Windows. If you have IIS or Personal Web Server running on your system, you'll want to stop it when installing one of these packages. Also, since these install the Apache web server, you'll have to make sure you shut down IIS before using Apache, and vise versa.
I've become a big fan of PHP and MySQL. You'll find that there are tons of open source scripts available, including more hit counters that you could probably keep track of.
Goog luck and have fun!