Here are some links for PNG websites.
These links will take you straight to the PNG sections of the Sites:
p.s There are many more out there but these will get you started because most of the Icons you guys ask for already exist you just have to look.
Always Happy to Help
WhiteDove
Excuse, but you don't say nothing of new.
I think that every member that request any image, on this site, knows very well or knows them soon during the forum posting, the sites that you've mentioned.
Creeed (I hope!) that, as I make, every time a member need an image, insert a post only AFTER have tried to search it on these (very popular) sites.
And finally, I think that one of the beautiful things of a community, is also is little given to make in order to help one with the other, not a simple "try to find it yourself here...".
Right ?
Aqua-Soft Forums