Here is all 512px icons of the Leopard.
ICO:
Every icon includes 16, 32, 128 and 256px image.
They can be used directly in Vista, because Vista supports 512px icon.
But if in the XP, it can only display 32px icon (Of course, you can Photoshop edit it by your self).
PNG:
If you need the PNG, you can open the [...]

A set of Mac OS X Leopard replacement icons
Developer: GlossII
File Size: 1.5MB
Download [1.5MB]

This is special edition of iLeopard Icons Pack series. All Leopard icons available in 512*512 pixels with 96 dpi.
For use with ObjectDock, RocketDock, RKLauncer etc..
Note:
All Leopard icons are property of Apple Computer, Inc.
Developer: kampongboy92
Download [15.2MB]

This icon pack comes with additional 105 .png images were extracted from Mac OS X Leopard. Its availale in 128*128 pixels with 96 dpi.
For use with ObjectDock, RKLauncer etc..
Note:
All Leopard icons are property of Apple Computer, Inc.
Developer: kampongboy92
File Size: 2.6MB
Download [2.6MB]

This icon pack comes with 150 .png images (include stack icon), was extracted from Mac OS X Leopard. Its availale in 128*128 pixels with 96 dpi.
For use with ObjectDock, RKLauncer etc..
Note:
All Leopard icons are property of Apple Computer, Inc.
Developer: kampongboy92
Download [3MB]

Drawer is a set of transparent PNGs to be use on your dock. Original OS X icons created by Optica Optima to be use for stack icons on Leopard Docks. Because the icons looks so cool, I converted it to PNG format so it can be use on Object Dock, RK Launcher or any other [...]

After much work I present pack “finished” of Antares. Pack includes 100 icons in formats PNG, ICO and ICNS at the moment all in single pack of 34.7mb but later i will separate in 3 so that the file is less heavy. Thank you very much to those people who have collaborated of [...]

Developer : GlossII
Download [729KB]

This is a leopard’s application icons in PNG format with 512×512 resolution. There are a total of 43 application icons in this ZIP.
Developer : MacCore.net Filesize : 6.52MB
Download [6.52MB]

3rd release of Leopard Refflective IconSet compressed file contains 25 pngs
Icons: Dom BootCamp DashCode Exposé QuickTime XRay Office Word Excel PowerPoint [...]