In 2003 the category labels, like Attention Line and Closing, are the
names of
paragraph styles that were applied to the texts when they were made into
AutoText entries. You can make a new category just by making a new style
and
applying it to the text, then selecting the text and pressing Alt+F3 to
make it
into an AutoText entry. Later, when you go to insert an entry, if the
cursor is
in a paragraph with one of those styles, only that style's entries will
appear
in the menu. Read
http://www.word.mvps.org/FAQs/Customization/AutoText.htm
for a
better description.
It appears that Word 2007 has simply thrown away this mechanism. Instead,
you
select any piece of text and press Alt+F3, and the dialog that appears has
boxes
for entering the entry name, the gallery (you have to choose AutoText; the
default is Quick Parts) and the category (which now has nothing to do with
styles; you can choose any existing one or make one up on the fly) as well
as
choosing which template to store it in.
Go to Word Options > Customize, choose the category Commands Not In the
Ribbon,
and add the AutoText item to the Quick Access Toolbar. That button will
show the
AutoText gallery, with the entries grouped by category.