I spent the last three months creating some brochures for my job (I'm not even a quarter done yet). One thing I found out is that you have to be careful of copyright when using images you find on the internet. The reason its taking me so long to create those brochures is because I need to find images that aren't copyrighted.
My coworkers husband is a website designer. Apparently he was sued last year for using an image he didn't have permission to use.
I'd really hate to see the same thing happen to anyone else.
I suggest taking whatever time is necessary to verify that it isn't copyrighted before using it.
If you're from the US, the below website might help you to find out.
http://www.copyright.gov/