Examples of  free Clip Art from 1ClipArt.com.  The site includes the following disclaimer.

"Some of the graphics in this archive were not created by 1ClipArt.com. The authors of the graphics in this archive may not agree in the use of their graphics in commercial projects. 1ClipArt.com does not take claim of ownership to any of the graphics in this archive and any use of them is at your own risk. If you have comments or questions about this archive or the graphics featured in it, please contact us."