All over the internet there are pictures, but most of them are copyrighted.  So when you design a web site make sure to give credit to the artist of the picture.  Otherwise you can get free clip art, which you do not need to pay for the picture.  It is free to use.

Here are a few examples:

Here are some links to the free clipart websites:

#1 Free Clip Art - Over 10,000 free categorized clip art images!

Barry's Clipart Server

Free Clip Art - Free Original clipart for the Web - Clipart for personal use.