From;
http://www7.buyoffice.microsoft.com/emea1/product.aspx?sku=10234528&cache=-892858711&culture=en-GB
Before you install, I would uninstall the trial version and reboot, (restart), the computer to complete the uninstall process.
Otherwise, any computer retail store, or some recognised online store like Amazon, for the full CD package.
Mark
I bought Office 2010 home and student with a 60 day free trial of Outlook 2010 which has now expired.
What is the quickest and easiest way to upgrade to the full version of Outlook?
Thank you

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic