I was going to post a request for that feature too. There are some iPhone apps dedicated to do just that and that go a little further and provide links to webstores (e.g., Amazon) and also get price comparisons, etc. But what I would use it in Evernote would be just to get product information. For books, what I do now is just to take a snapshot of the ISBN and look it up later, but I have currently the need to get info for other products... not just books. The feature is present in a competitor product: springpad.