Contact your financial institution right away. Explain what's happened & that you've been scammed into buying a free application. Hopefully they will be able to help you out.

And some of the earlier posts in this thread have info from other scam victims.

I couldn't find much about againstadware.com but there's a bit of info on this page: Introducing: Roguevertising

Good luck - I hope that you can be reimbursed. Let us know how you get on.