Where is the Gnome-Shell Shutdown options

Solution 1:

If you hold down Alt the Suspend option becomes "Power Off".

Edit: Although I should add that I use gnome-shell and I prefer to use an extension to add the power off option to the menu without having to hold alt. Webupd8 offers the "Alternative Status Menu" extension which adds Power Off and Hibernate options to the menu permanently.

Edit2: There is actually a site for gnome-shell extensions that provides some needed extensions. The site is located here and there is an extension for an alternate menu that contains "Power Off" by default. If you're running gnome-shell you can go there and just flip the switch from off to on and then confirm that you want to install the extension.