Need a cheap focus lens for Nikon d3000?

I got the Nikon D3000 and I want a focus lens. It can't be over 300 dollars and I don't think my camera is compatible with AF lenses. But it does work with AF-S lenses. I've been looking online everywhere and can't find anything.

Nikon's 18-55, 18-70, 18-105, 18-135, 55-200 and 35mm f1.8 all are quite affordable and all autofocus on your d3000. Without any indication whatsoever on what you want your new lens to do this is as specific as I can get.