Changing the system icons

Nope, Candybar 2 doesn't work with Leopard at the moment. However, Candybar 3 is supposed to be fully Leopard-friendly and is slated to be out before the end of November.

You can manually change regular folders easily enough in the meantime...

1. Select the icon you want to change your folder, app or file to.
2. Choose "Get Info" from the File Menu, or click command-I.
3. Click the icon in the upper left of the info window.
4. Choose "Copy" from the Edit menu (or type command-C).
5. Select your folder, app or file on the desktop and "Get Info" for it.
6. Click the icon in the upper left of the info window.
7. Select "Paste" (command-V) from the Edit Menu.

This doesn't work for certain icons unfortunately, such as the Finder and trash. You'll either have to wait until the new Candybar is released or do some fiddling about with your system files. I don't have a copy of leopard myself so I can't advise you on the latter, I'm afraid.