Pior to OS 10.10, Yosemite, all versions of OS X shipped armed with Network Utility and RAID Utility as standard.
The default locations of these applications was found in the /Applications/Utilities/ folder on each OS X.
Now with Yosemite, these applications are noticeably missing.
Good news though, Apple did not remove these applications. A quick way to find and launch these applications is to launch Spotlight and enter the corresponding application’s name in the Spotlight field.
Otherwise, these applications are now buried within the following folder, /System/Library/CoreServices/Applications/.