Is there a way to get the icon used by a given window?

All, I'm working on a proof of concept replacement for the 开发者_Go百科windows taskbar. (Mostly for my own amusement than anything else) However, one thing I was not able to find was a means of getting the icon a given window is using. I'd be especially interested in a way to do this using a built-in dll, though at this point I'm looking for anything pointing in the right direction

WM_GETICON ?