I think you can add the shutdown launcher to the desktop by right click create a launcher and
use the command xfce4-session-logout.
Or to be sure under the command browes to /usr/bin where the xfce4-session-logout is located.
Check your installation which panel, desktop etc did you install i.e: opensuse or upstream, one or the other has a missing logout in the xfce application menu.
You can add the logout launcher also in the panel by mouse right-click and add the action buttons. Check the xfce-panel-plugin installations.
I used keyboard settings to attach xfce4-session-logout to ctrl-alt-del. That too works fine.
By the way, there are some very nice xfce panel monitors for cpu, network and harddrive. I’m very pleased. I’ve seen only one very minor xfce problem: When I use the cursor keys to move around the desktop, I get stuck at the icon at (0,0).
I expected Gnome to be lighter than KDE, but the opposite was the case: It uses even MORE resources. Then I had a lot of difficulty setting Gnome shortcut keys. I needed to use gconf-editor. Apparently the gnome control panel settings are ignored. Finally, I kept tunning into the 10-year-old vertical panel freeze bug. That’s when I decided to try xfce. Glad I did!
The openSUSE 11.4 xfce version is 4.8, supports drag and drop of application from the xfce menu to create a panel launcher. The panel transparency now is much better than the previous releases.