Web-form for adding subdomains?

[Ballistic509]

Okay, this is going to be a project for me. I need to know all the files that are used to write subdomains, adding users, and whatever else I may need for this to happen in apache and bind. I don't mean the page addresses, I mean which tpl, or php file should I review to do this? I know a couple but I really don't want to do everything, to find out it don't work because something I'm missing in one little file that I overlooked.

Can a developer or someone list which files include code for adding users and the such please?