Since you didn't list what it is you are after, we can't be specific about how to search. However, I went through Ebay's catagories until I got to Radio Control and bookmarked this location. Then, when I go to the bookmarked page, in the search engine box, I type in things like Airplane kit, ARF, Airtronics radio, Airtronics servo. ect. Generally, I get lists of 25 to 200 or so items to page through.

At the R/C start location I've bookmarked, I can also type in Balsa USA, Pica, or some other manufacturer and get specific infromation about products people are offering for sale by these manufacturers. I attempt to be very specific in my searches and feel if a seller doesn't understand how to list to get good exposure, I guess I didn't need what he was selling, anyways.

Be aware that if you type in brands, like Airtronics, many people will put Airtronics in their title, even though they are selling JR equipment. Although this provides them with good exposure I don't care for this action as when I typed in Airtronics, that is what and all I want to see. I know JR exists and if I wanted to visit JR, I would type in JR.

I have both bought and sold many items on Ebay and have had good luck with it! Good deals can be found, however airplane kits do not seem to be one of them!