Clipart
You can always subscribe to a site like
www.clipart.com or any of a multitude of other ones. This site,
http://www.clipart.net/, even has a list of a whole wack of free clipart sites. Barring that, office supply stores offer cheap disks loaded with lots of images.
If you have a specific image that you want, you can go to Google, click on images and type in the subject of the image you want. Once you get one (and it is public domain and not copyrighted), you can run it through a trace program and clean it up.
good luck
andrew
ps... we have images like that here but the forum frowns on trading intellectual property (which is a good thing)