Originally Posted by Reno Bay
Actually, google is not recommended for finding reference photos. Google doesn't own the photos that its searches put out. Most sites containing the photos that google finds have copyright statements on them and using those images for anything (be it personal use, commercial use, reference photographs, etc) would be considered copyright infringement unless otherwise stated, and if the person using those photos was discovered the owner of the photographs would be able to take legal action if they so desired. That is why I always search for stock photographs with creative commons licenses on Flickr and Deviantart.
On topic, I don't have any great action shots of my boy...he's a lazy butt.
Reno, you are allowed to use reference photos as references for personal use without permission, the problem is if you distribute your drawing (either commercially or non-commercially). So you can definitely Google any images and use them for practice. You can also get inspiration from a photograph and create an artwork for distribution, so long as the new artwork is substantially different from the original (e.g. Combining multiple photographs, changing angles, making substantial changes to the light on the subject, changing the background and generally making it different enough from the original so that they no longer bear strong resemblance).
Back when I had time and a life and all I used to draw horses a lot. Some of them would be from imagination or life sketches but I also drew from copyrighted photos. Drawing straight from a photo can be a bit easy and boring so what I did was imagined the horse in the same moment but from another angle (e.g. If it was galloping right to left I imagined it coming on a 45 degree angle left to right toward me). Or I'd imagine what the horse would have looked like a split second later in the stride, or with a rider aboard. These were all great exercises for me and improved my drawing from imagination no end, so I no longer need a reference photo to draw a horse.