Book Brush offers options to create your own Amazon A+ content. You'll find these options when you click the Amazon Logo under Ad Sizes in the Custom Creator.
Here's a link to a short How-To video: Watch How To Create Amazon A+ Stacked Images Now!
We also get a lot of questions about how to upload Amazon A+ content to your account once you've created it.
Here's a How-to video on that topic, too: Watch A Handy Guide to Uploading Amazon A+ Content to Your Account