Adding functionality to the admin cp

[TOA]

You can look at the your_admin_dir/modules/ as your reference.

Yeah, I found those files. I'm just not sure what to do with them. The one in question would be the users file. I want to add a subtab after Merge Users in the Users and groups part.

Do I just add code to that file for what I want it to do? Or do I write a new file and just dump it in that folder?

What happens when there's an update?..Do I have to go alter it again?

Thanks for the help both of you. This can get a bit overwhelming trying to trace everything down so I'm glad there's help available.