The green guy in the door is the default xfce logout icon.
What I did on my xfce desktop was to make a second panel, docked at the bottom of the screen. If I right-click it, and choose "Panel Preferences", then on the dialog there is a tab named "Items". On that tab I can add or remove icons, and the logout icon is one of the "action" icons that you can add. So I have the logout icon on Panel 2, and that is where I log out or shutdown the system. On my system, Panel 1 is a conventional "taskbar" style panel, with the desktop switcher, wicd, battery charge, etc. on it.
I don't know if that answers your question, but it is my way to set up xfce with a logout icon.