Outlook 2002 *is* the latest version. You can not legally
download any version of Outlook anywhere. It's commercial
software that's for sale, not given away.
As already mentioned, you can do a repair install or uninstall/reinstall
from your Outlook or Office CD. Just wanted to add that any additional
updates available for that program will be at the Office Update site.
One way to reach that site is to open Outlook open and click on Help.
Select the Office Update option from the menu that appears.