Amazon.com handles all Kindle technical support, and you can contact the tech support department by phone or online. To contact tech support online, navigate to Amazon's Help & Customer Service page and click "Contact Us" on the left-hand side.
This contact page allows you to decide whether you would like to contact technical support representatives through email, phone or live chat. Before contacting technical support, you may also use Amazon's self-service links to try troubleshooting on your own. You can find these links by clicking on your Kindle device on the Help & Customer Service page, then scrolling down to Quick Fixes.