[CentOS] CentOS 7 User Manager Tool

I have CentOS 7 installed with GUI (Gnome 3.8.4) and I'm trying to
follow the guide at
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/System_Administrators_Guide/s1-users-configui.html

it speaks of "System > Administration" from the GUI or
"system-config-users" from the command line, but I can't find either?  I
don't have a "System" top menu, only "Applications" and "Places", and
when I try the command line option I get "command not found".

any ideas?  TIA!

-- 
Igal Sapir
Railo Core Developer
http://getRailo.org/