Strange - looking at a lot of the icons, like the ones following, they certainly must have been designed to resemble Windows icons, but I can't find the exact icons they're modeled after. I'm really not sure where these would stand, as far as copyright goes - a number of them have enough resemblance to real Windows icons (or other trademarks) that you'd probably get legal grief for trying to use them in your own product, for instance.

http://www.iconfinder.com/icondetails/7043/128/aim_icon

http://www.iconfinder.com/icondetails/7121/128/sonic_icon

http://www.iconfinder.com/icondetails/7175/128/folder_window...

http://www.iconfinder.com/icondetails/7365/128/staroffice_ic...

http://www.iconfinder.com/icondetails/7394/128/users_windows...

http://www.iconfinder.com/icondetails/7563/128/lib_wine_icon

http://www.iconfinder.com/icondetails/7609/128/mp3_sound_ico...