Hi Charel,
If you right click on the front panel of your vi you should get a pop up of the controls palette or go to the "Windows" top menu and select "Show Controls Palette". In the middle of the controls palette is a sub palette labeled "Containers" and the first item listed is the "Tab" control. There also is a "Dialog Tab Control" listed under the "Dialog Controls" sub palette.
hope this helps
cheers,
--Russ