What versions of OS X support 'Find My Mac'? I am running a clean install of OS X 10.9.5 (Mavericks) and can't seem to locate the 'Find my Mac' feature that I have seen on my friend's machine. 

What versions of OS X support 'Find My Mac'?
The minimum version of OS X that supports Find My Device is 10.7.5 (Lion).  See this Apple Support page for more details.

The setting for Find My Mac can be found under System Preferences > iCloud.  See this Apple Support page for full details