This is hard to describe, but there is a site that monitors web activity for many images of yours, and includes legal aid for infringement etc; but it's become a large monthly fee.
If you use Google images, you can drag an image at a time in for free to see whats going on at least.
I imagine there must be some economical site or service that one can bulk upload images just to monitor what is going on-- without the legal hlep? Anyone heard of anything? Thanks.