We hear this question from our clients often. The answer is almost always NO!
You cannot download and use photos from the internet unless the site specifically states that you may download photos and specifies the exact conditions under which you can use them. For instance, you may be given permission to use a photo for personal use. Placing that photo on a commercial site violates copyright code.
What if the site doesn’t say the photo is copyrighted?
It’s copyrighted anyway. You may be surprised to learn that when any U.S. citizen creates anything new (original), that work is automatically accorded a copyright. No forms, registrations, or applications required. It just is and the new photograph is protected even when the photographer uses it on a website without an explicit statement of copyright. The creator must be able to establish that s/he created the artwork. The most common way of doing this to demonstrate that s/he snapped or used the picture prior to an infringement by someone else.
So where can I find free or low-cost photos for my website?
Try www.photoexpress.com, www.istockphotos.com or www.fotolia.com
For other materials to share, remix and reuse legally try http://creativecommons.org
If you are a serious artist, writer or photographer, you will want to look into additional protections for your work before risking it on the Internet.
In any legal matter, always seek professional advice.