In Office Word 2007, they don't call it Auto Text. They call it Quick Parts.
Open a Word doc, type in what you want to save as Autotext, hight light it
and then go to tab "insert", then Quick Parts, then name the text you want to
save and it will appear in a text box there. Then any time you want to
paste/insert it into a document you are working on, just insert your cursor,
to to the "insert" tab and over to the Quick Parts, then click on the text
you have saved and it will automatically be pasted into Word.