Form manipulation via Process

Does anybody know how to manipulate the attributes of a form (Visibility, Minimize, Maximize, etc.) when you have the process. For example:

Dim proc() As Process = Process.GetProcessesByName("notepad")
If proc.Length > 0 Then
Dim p As Process = proc(0)
'How do I get control (if possible) to be able to manipulate the form and
'or send form events to it?
End If

This article: here should get you started

here is an example.

The only thing it doesn't do, is if you set the window to invisible, its still running as a process in the background, and you can't make it visible again. (you need to end the process)

I am sure there is a way to do it, however I don't have time to mess around with it at the moment..