Programatic desktop icon placement

I am looking for a way to programatically get/set the icon positions on the desktop. Clearly there is some "state" stored in a somewhere. Does anybody know here?

I am trying to get a proof of concept going on ANY platform so if you know how to do it on XP in gnome, KDE or Mac OS I would really like to hear about it.

How do I arrange my desktop icons spacing?

Start the Display Control Panel applet (go to Start, Settings, Control Panel, and click Display). Select the Appearance tab. Under Item, select Icon Spacing (Horizontal) and modify the size. Select Icon Spacing (Vertical) and modify the size.

How do I align my desktop icons to the grid?

Right-click any open area on the desktop. 2. Point to Arrange Icons by and click Align to Grid. To disable the settings, click Align to Grid again.

Start here: http://msdn.microsoft.com/en-us/library/bb773177(VS.85).aspx

It's unfortunately quite a nasty API because every object in the shell is identified by a thing called a PIDL, which was created by Satan himself to confuse anyone trying to avoid access violations and memory leaks.