EDIT: I changed the links around. Should be easier. Thanks Stephanie!
After downloading the free Amazon Local smartphone app, you'll get a free $2 Amazon mp3 store credit. You'll want to look for the image above, which should be found halfway down the page on the left side. You'll then be able to redeem your credit at Amazon.com.
This offer is good through today only and you'll have until April 5 to use it.