If you're making 3d surfaced parts in AutoCad and saving them as DXF or STL, then DeskProto will be able to read them and write rastering toolpaths to cut them out. It has an Anilam postprocessor, so you're covered there. They have a basic version I sell for $250, but the full version, (which supports 4-axis milling, among other advanced features missing from"Deskproto lite") costs a bit more. You can try either for free by downloading a demo from
www.deskproto.com; it will time out after 30 days.
If you're trying to convert 2d drawings to G-code, DeskProto won't help: it just recognizes polygon-mesh surfaces. Doug Yeager wrote "Ace Converter" that converts drawings to G-code: you can download it for free at
http://www.yeagerautomation.com/ace.htm ; as far as I know it is totally free and doesn't expire. If you try it, let us know how well it worked for you. Of course there are other programs that can do one or both of these functions, but usually you have to pay for them.