GDC: Hands-on with Valve's Newest Steam Controller Prototype - IGN
Amazon.com: TouchProtect for Steam Controller - Enhance Tactile Feel, add Style, and Protect Your Trackpads. for Steam Controller and Vive Controllers (Hex - Black) : Video Games
Thumb Stick For The Steam Controller, Touch Pad Stick Analog Stick With Precise Movement Control For The Steam Controller - Accessories - AliExpress