The IconSeeker.com is an excellent icon search engine, it contents about 50,000+ high quaility icons and each icon has PNG, ICO and ICNS formats for Windows, Macintosh and Linux Systems. Much of the icons are larger than 128px, so it really fit for Win7 & Vista.
Site Url: http://www.iconseeker.com
Search Results of "Vista"
All the icons can be free used for non-commercial, but part of them copyright belongs original author, if you want to use icons for commercial purposes, you have to pay for obtain the author's License agreement.
