Where do I get serial numbers (keys) for products I've downloaded from Imagine (formerly DreamSpark) website?

Answer: 

Sign in to the site (http://e5.onthehub.com/WebStore/Welcome.aspx?vsro=8&ws=82FE585A-DB9B-E011-969D-0030487D8897) on the top-right where it says "Sign in".
Click on the SOFTWARE button found near the top of the page.
Choose the software in question and click the LINK found under Deliverable (i.e. Download, CD Check Out, etc))
You should be able to see all of the software details information including the serial key number (if one is required).