Do you mean this app Dramatic Blank And White HD from the iTunes app store ? If it is that app (in which case I don't know where cnet comes into it) then it should have downloaded into the Apps part of your computer's iTunes library, if you want to use the app then you will need to sync it to your iPad, or download it directly on your iPad via the Purchased tab in the App Store app on it.
Apps that are downloaded from iTunes are only compatible with iOS devices, iPhones, iPod Touches and/or iPads - that particular app can only be used on iPads (an app's requirements are listed below its description on its page in the store). If you want to use programs on your Mac then you either need to buy them online or from the Mac App Store.
As you don't have an iPad then try the 'report a problem' page to contact iTunes Support and see if they will refund or credit you : http://reportaproblem.apple.com
If the 'report a problem' link doesn't work then you can try contacting iTunes support via this page : http://www.apple.com/support/itunes/contact/- click on Contact iTunes Store Support on the right-hand side of the page, then Purchases, Billing & Redemption