Hope this helps, just coded it. MEGAUPLOAD - The leading online storage and file delivery service
It gets all the files in the selected directory and sets into an array, after that its just a case of selected each item, this only gets the Magic and Path, and sets into the listview
Its an example to show you what to do, now you can add on other stuff.
If you want I will add the part to read the gpd name.....?
Also if you just want it for the GPDs then just in the reading put
if (reader.readstring(4) != "XDBF") return;
Edit: also to get the selected tree node its TreeList1.SelectedNode; (thats for the first column,  for the secound etc etc)