icons

I'm looking for some good 3d icon and system themes, especially for GNOME if possible. When I mean 3d, I mean in the sort of stuff like old school MacOS interface system icons or WIndows Vista. Things that have some depth, shadows and and colorful. Examples:

Hey, I was wondering if it was possible to create a custom themes using 48 * 48 pixel png images as icons. I don't know how to CREATE a theme. I don't find any answer to that in the internet. I will continue to create the theme icons only if I get a confirmation answer. It's ok to just modify...