It’s very simple! Use this web proxy and…Sign up Here. The proxy is required because this offer is for a select region. The page is open for registration though. If you get an error message about your region, then make sure to disable cookies and so forth via the proxy. When you complete registration, a key will be available for download. Download the key AND Avira Premium Antivirus. Links for both will be given through the URL sent to your email address — so use a VALID email address. The download page for Avira Premium can also be reached Here. I have no clue how long these keys will be available so act fast.

Edit: This method is dead. Check for new ones at Free 3 Month Avira Premium Security Trial page.