There’s a pretty cool tool for doing competitive research that shows you which ads a given company is running: The Facebook Ads Gallery by AdEspresso.
Now it should be mentioned that their database isn’t complete, and their data isn’t 100% accurate.
Especially if you’re with smaller advertisers, you often will find that they don’t have their ads in their database. It’s still a useful tool though.
It’s very easy to use and straightforward:
You just type in either a URL or a company name or a keyword. I find that the keyword search is, after the URL search, particularly useful, since it will often yield more results. While the relevancy isn’t always as tight, you’ll still get plenty of ideas from doing so and might come across companies you wouldn’t have otherwise thought of.
The results page is organized like a gallery, with pinterest-style pins.
Clicking on any of the ads will give you further information, like the actual ad itself, the link of the destination URL, the associated Facebook page, the Placement, Objective, Special Attributes, Industries and other data.