For some reason I can't use MacPorts. So the question is if it's possible to install Apache, PHP and MySQL on Snow Leopard w/o using MacPorts?
Please don't offer MAMP or other bundles.
Thanks in advance.
Yes, Apache and PHP already come by default with a Mac OS X installation, and you can download an installer for MySQL on their website.
For a configuration guide, have a look at this related answer:
How to turn Mac OS X Lion into a web server?
The linked answer also applies to Mac OS X Snow Leopard.
Another popular (and imo superior) way of running development environments is running a Linux server with your preferred configuration in a VirtualBox virtual machine. Vagrant makes this workflow even easier. This is a very flexible solution, as you can easily add custom extensions and more specifically for one project, without messing with one centralized install.