Here's a few samples. To play or download the midis on this page, just click the link. If you leave the window open the sound will continue while you browse other pages. If you have the Crescendo player it just takes a click. There are more midis on Free Midi Music from Gospel to Motown page.
Some sites carry thousands of midi files.
Here's a few of the best I've come across, and you can follow their links from there. The Midi City - very nicely built midi site.