FADEC and auto-throttles are different things. FADEC integrates throttle, prop and mixture (in a piston engine) into a single power lever. Continental has done a lot of work in this are, and Lycoming now has a FADEC engine in their new TEO-540 engine, which is so far slated for UAVs and the experimental Lancair Evolution. Jets also have FADEC.

With FADEC you only have to move one power lever to control the engine, but you do have to move it yourself. With auto-throttles the power lever is connected to the airplane's autopilot, so the A/P can adjust the throttle setting as it sees fit to fly the airplane. Cirrus is working on an auto-throttle setup for its planes, but that is for somewhere down the road. Right now auto-throttles are only found in airliners and high-buck biz jets.