Can't find System files or folders using Spotlight? Unfortunately, you can't use Spotlight in the upper right Main Menu to search System folder or files, but you can search for them in Finder.
First, open a new Finder window, go to "File" and click on "Find..." or you can type Command + F. Another search bar underneath will appear under the search bar. Click on where it says "Kind", then select "Other...". It will bring a list of options for various ways of finding and/or filtering your search results (handy huh?), then select System Files check mark and click "OK". Be sure to make the bar next to Kind that says "don't include" and change it to "include". Now search and find the System files and System folders you want.
Remember, this will only work in a Finder window, not in Spotlight in the upper right Main Menu of OS X Leopard.