The LabVIEW Wiki actually has better information on this than the LabVIEW Help.
enumerated variables:
http://labviewwiki.org/Enum
typedefs:
http://labviewwiki.org/Typedef
Note that the control must be in a .ctl file to become a typedef. There's two different ways to do that.
Create a new control by going to file menu and selecting "New...". The following dialog will pop up. Select "control" and click OK.
OR
From an existing control, right click on the control, hover over the "advanced" item on the right-click menu, and select "customize".
This will still create a new control, but it will be the control you selected (though you can always delete it and place down something else).