PinterestThis is a great option if you aren't sure of exactly the right words to use when looking for a particular style. The "More like this" function can be really helpful, too, in focusing your results.
RED FLAG: If you're going to use an item in your research, make sure that the link goes back to a museum or archives website who owns the item, or something identifying where it is held. Many Pins on Pinterest are just photos that have been connected to spam or unrelated websites, and they aren't stable to cite for a paper. Also, be aware that the picture may be of a costume, even if it's historically accurate and displayed in a museum.