I am not worried about whether this is in Winforms or WPF.
Is there ANY way at all that I could develop my own user control like the one found in Microsoft Paint, below:

If you can’t see the pic above, it’s here: http://img232.imageshack.us/i/txtboxlblctrl.png/
Is there anyway at all I can do something like this in C#?
Thank you
Sure you can. By developing your own Usercontrol you can do nearly anything.
I think the easiest way would be to use a WPF TextBox and alternate it with a template.
This [http://img199.imageshack.us/i/textboxu.png/%5D is what you get by simply using [http://img163.imageshack.us/i/stipe.png/%5D as BorderBrush