To be honest I haven't found any 'great' Windows icons - excepting Preemo? I have a set of icons called Preemo - I got from somewhere that I can't remember - if you haven't come across them I could email them you. They are system icons like folder, recycle bin etc.
Other than that I use IconSucker (free from CNET I think) to extract .ICL files.
If you turn anything over in search I would be grateful to know!!!