There are quite a few samples in the blog archives, which you can find by using the Samples Topic.
I’ve also put together some samples from recent books I’ve done, and these are available as PDF downloads. Here are the links. You can click them to download the files or right click to save the file to your PC:
TheBookDesigner.com Book Cover Design Samples
TheBookDesigner.com Book Cover Interior Samples
Thanks for your interest. If you have any questions about design issues, please email me at jfbookman at gmail.com.