L,
You can use the "Increase Indent" command. I believe that the button is
built-in but not generally available. If you right-click on a commandbar,
select "Customize.." then select the "Commands" tab, "Format" category,
about halfway down the "Commands" listbox there are two buttons that you can
drag and drop onto any commandbar: "Increase Indent" and "Decrease Indent"
HTH,
Bernie
MS Excel MVP