Most of the icons are indexed here as well:
http://www.iconfinder.com/search/?q=iconset%3Anounproject http://www.iconfinder.com/search/?q=iconset%3Anounproject_co... http://www.iconfinder.com/search/?q=iconset%3Anounproject_np...
They are grouped by the different authors which makes it easier to find out what license applies. You can search in the different groups by adding a keyword e.g. http://www.iconfinder.com/search/?q=iconset%3Anounproject+pl...