I am a contributor at the new photography website www.pixiq.com Here is an excerpt from an article I recently posted. Visit the Pixiq site for many articles by many contributors. It will broaden your photography knowledge.
Have Your Images Been Stolen?
Internet photo sharing is here to stay, and any photographer that wants to build a name for him(her)self needs to upload photos and put them in front of as many viewers as possible. Sure, it’s a risk — the more viewers the greater the chance of image theft. Not only is it copyright infringement, but it makes it harder for the professional photographers to put groceries on the table.
Can it be possible to find who is using your images? Now there’s an answer, at least a partial answer. www.TinEye.com is an image search engine that uses image identification technology to find exact matches of the image you ask it to search for. It’s as easy as right clicking on your image and asking TinEye to search the more than 1.7 billion images in its index for an exact match. It doesn’t matter if the original image has been resized, edited or cropped — TinEye will find it. Although the creators of TinEye at Idée Inc. work hard to add millions of images each week, there are still many images to be added to the database.
TinEye was able to find a bunch of my images being used without permission. Some were part of blogs: “Look, here’s a cool pic,” which I really don’t mind if they include a link back to my blog; however, some were downright copyright infringement and used for commercial purposes.
Good photography only comes with lots of effort and time, and it’s frustrating to see how easily others steal images without compunction. Look at the images below. They are the originals. In the “old” days thieves would scratch out the serial number; now there is no fear — how bold.

This image "Breaking the Rules" has lots of commercial appeal. I'm not surprised when I see it ripped off for an entreprenurial article. Hmm... they didn't list stealing images as a hot tip.

They did some weird color adjustment on the right image. I wonder what they added in the bottom right corner? Could it be someone taking credit for the image?

This image is often stolen for dating and relationship sites. I need to Email Yogi and tell him about copyright infringement laws.

This theft really gets me mad. They are big business with a big budget. They are well established in Austrailia and have many high end clients. There is no excuse for this theft.

Watch out, your travel photography is in demand. The pic on the right is mine, the pic on the left is not mine but I did find the travel photographer that took it (I used Tineye). If I had her email I'd contact her.
Bert Krages is an attorney and photographer. He handles copyright enforcement as well as other issues like photographers rights. Unfortunately, its a few hundred dollars to have him send a letter and no guarantees of ever getting compensated for the illegal image use. If it does go to court (rare), courts typically award between $750 and $30,000 per infringed work. http://www.krages.com/