hi andy
if you want a static date (ie when you open the workbook tomorrow it has
today's date) then click in a cell and press
control and your semi-colon (

key
and then press enter
the format that you get is the default format set under regional settings
you can change the format by right mouse clicking on the cell, choosing
format cells
clicking on custom (on the numbers tab) and in the little white box on the
right hand side typing
mm/dd/yyyy
(you might find this already done for you under the date section)
if you want a dynamic date (on that changes each time you open the workbook)
type
=today
in a cell, and press enter
then do the formatting the same way as outlined above.
Cheers
JulieD