Many, many sellers on E-bay do not use correct catigories, so if you detail your search too much, you can miss a lot of good stuff. Start out in Toys & Hobbies, Radio Control, then use the left side of the page to gradually close you search parameters. You can choose aircraft, cars, electric, gas glow, RTF ARF Kits etc.
Or you can start out in Radio Control, and then type "plans" etc into the search bar.