It's pretty easy to find banners to use for inspiration or as a source for your own designs using Google Image Search. First you need to be familiar with standard banner sizes. They're set by the IAB (the Interactive Advertising Bureau) and their latest display ad guide is here: http://www.iab.net/guidelines/508676/508767/displayguidelines A nice size is the 728x90 leaderboard. To find those with Google, go to image search, search for a keyword related to the niche you want a banner for, and set the image size to exact, 728 wide 90 high. You'll get a result like this: Voila, thousands of banners to inspire your own designs.