I've noticed that the info on this page is outdated. How to Perform a Ping Test (Mac OS)
If you are running Mavericks, Network Utilities is now hidden here: /System/Library/CoreServices/Applications/
You get there like this:
In there you'll find Network Utilities: then you CTL+click it and make an alias, move this alias to the
Utilities folder where you can now easily access it.