This is an icon made from the apple in my desktop wallpaper [link]
requested it, and it seemed like a simple and reasonable request, so here you go. Both ICNS and ICO versions included.
EDIT: Since the source was nicely layered and KabitoJak asked so nicely I've uploaded a new version that has distressed and clean versions of the icons.
EDIT: theBassment pointed out that the shadow caused some visual issues on the new Mountain Lion dock, so I took a few minutes and updated with shadowed and non-shadowed versions in the zip.