Hi Katy, if you scroll down to the bottom of the listing, there should be a small link to "Report this item to Etsy", from there, a pop up window will give you a choice of reason for reporting and you can select "this is my intellectual property" choice, follow the prompts from there.
You MUST go through these steps in order for Etsy to take action. Once that happens, Etsy is usually pretty quick to take things down.