Gifart.com has a very large selection of the brightest, sharpest sports clipart you can find online. There is also larger art for use in Powerpoint Presentations and animated gifs. This is not the same old sports clipart you see everywhere else, either, and it is copyright-safe and royalty-free. Use it on your personal site, your commerical site or your business presentation.
A few samples...

Clipart.com has a large selection of high-quality sports clipart with over 7700 results returned for the search term "sports clipart" but there is almost any type of clip art you need here as well. It's a subscription service but it's well worth the price - I've been a member for years - and the images can be used on a commercial site. The images are all online so you get instant access and the nice thing is that there are many different styles of art to choose from. Some examples...