Since writing the article on the hidden Wi-Fi diagnostic tool in Lion and Mountain Lion, I’ve gotten a few emails from people who haven’t been able to find the CoreServices folder in Lion.
Here’s a trick on how to get to folders that are hidden: Within Finder, go to the Go menu and choose Go to Folder. In the window that opens up, enter the following: /system/library/CoreServices
This should get you to the right folder. You can also use this trick to get to your hidden personal Library folder. Just enter: ~/Library