This article is from the Miscellaneous Macintosh FAQ, by Elliotte Rusty Harold email@example.com with numerous contributions by others.
Your icons have passed on to a better place, but with a little
magic it's normally possible to resurrect them. Several utilities
including Norton Utilities for the Mac and the freeware drag-and-drop
utility Save-A-BNDL should retrieve your icons. See
Rebuilding the desktop (Question 4.3 in the Introductory FAQ)
should also restore your icons.