How do you contact the webmaster of a site to get a picture you made taken off of Google Images?

In other words, how do you contact the webmaster of the site you put your picture on? I tried removing it by requesting a removal by Google but they denied it and said that I have to talk to the webmaster of the site I put the picture on. How do I do that?|||go to the website and find the link to contact them or their webmaster