Jynx made a good effort, but the listbox that tutorial shows you isn't the best, for example the scrollbar thumb doesn't change size as you fill the box with data or remove data from the box, and it has no up/down arrows.
It's good as a basic tutorial but to create a decent functioning listbox, you'll need to put in more effort than that. I would also think about writing some kind of control that can be used in any window as many times as you like, because if you then decide you want another listbox you're going to have to duplicate a lot of code.
Not trying to put a damper on things but it's a simple thing to do, at all.
