One thing you can do to try and track your Etsy pins:
Check out your Shop Stats. If Pinterest shows up as a traffic source, click on it. Check out the Landing Pages at the bottom of your Pinterest inbound link stats page. See which of your items appear as landing pages, then search for those items using keywords on Pinterest.
This doesn't always work, but can help ID where some of your items are.
You can also search for your website directly by typing the URL:
http://pinterest.com/source/mywebsitename.com/(and fill in your website name, obvs.)
For instance, pins from my website show up when you go to:
http://pinterest.com/source/backgarage.com/I wish there was a way to directly track pins from particular Etsy shops, though.