I don't know how the procedure is to download the demo. U fill in a form on the "Autodesk Maya Personal Learning Edition Download" page and you are probably able to download it from the next page.
It's a fully automated system and if there is a e-mail confirmation, u should receive it instantly. Could it be that your cousin mistyped the e-mail address?
If any problems with the site, u should contact discreet.com.