...or login into www.autodesk.com/subscription login to get your official copy and serial number.
Remember...Autodesk is not shipping subscription customers their software. You MUST download the new versions online.
Hope you don't have dialup connection speed.
Try AutoCAD 2012 FREE for 30 Days
About the Trial Download
Your trial period is 30 days from the time you install your product.
The trial download uses Akamai’s Download Manager. The first time you download a product trial, you will be prompted to install the Download Manager. Learn More
AutoCAD 2012 Trial Download FAQ (pdf - 92Kb)
*Free product trials are subject to the terms and conditions of the end-user license and services agreement that accompanies the software.