This site (icons.mysitemyway.com) has many bundles – all free and all easy to look through, and download. Another thing that’s nice about this site is that *All Icons Etc. royalty free stock icons, and stock clipart are free for use in both personal and commercial projects. Most sites that offer free icons only allow for personal, not professional use. This is open to commercial projects as well.
iconspedia.com has a pack for the iphone bundle that’s quite nice here:
Free icon sets (www.iconshock.com/icon_sets)
– this site has icons you can purchase, but also has a free section which they add to each week:
www.iconarchive.com has some nice free icons & sets – but most you have to download one at a time instead of downloading the whole set in a zip or one click.
This site has a few: www.cruzine.com/tag/icons/
I like the monsters :p
Designmoo – icon sets that usually include the designer’s psd or ai file.
Design Kindle has a few nice collections as well. Here though, what you see is what you get there are no psd or ai files to download. Images only.
View them here:
deviantart.com also has some nice sets if you’re willing to look – but if you’re digging beyond this list you’re probably looking for something specific enough that you should just design it yourself 🙂