I just found out that one of my photos is being used without my permission in a promo video by Colorado Springs-based ad agency, Vladimir Jones. (Thanks to an anonymous tip!)
In this case, I decided to file DMCA (Digital Millennium Copyright Act) takedown notices with YouTube and their ISP.
Prior to doing that though, the first thing I did was take screen shots of the usage (including URL) as proof:
Next, I used YouTube's Copyright Complaint Webform, found via their YouTube DMCA Policy page to report the violation.
I then needed to determine who hosted the infringer's web site, which I found out to be GoDaddy by searching their domain name at Whois Lookup | Whois.net. This led me to find GoDaddy's trademark and copyright infringement policy, which directed me to send a DMCA-complaint letter (or email facsimile) for their review.
If, like me, you find yourself in this kind of situation and need good sources for DMCA takedown examples, check out these versions that I used to form my own copy:
How to Send a DMCA Takedown Notice | Black Star Rising
Sample DMCA Take Down Letter | IPWatchdog.com | Patents & Patent Law
Related: Calanan Photography: Found my photo used without permission (by Toyota)