http://www.earcentergreensboro.com/hearing-implants/envoy-esteem-device/index.php

The Ear Center of Greensboro's website provides a lot of great information, not only about the Esteem device itself, but also about what to expect during and after surgery. They inform you of the risks of the surgery and certain things that need to be avoid once implantation has occurred. The site also goes into the science of hearing which allows future patients to truly know how the esteem works.
This site provides a lot of information and is easy to understand. It's sectioned off so you don't have to hunt for information.