Hello oh wise and informed Mach users!
I am a luthier, (maker of musical instruments). I am entering the world of CNC and having fun so far.
I have built a 25”x 37” router table: (
http://www.solsylva.com/) with xylotech steppers and controller and a ¼” spindle. I am using a demo version of Mach 3 (which I will upgrade to the full version as soon as I am sure that this is a good move.)
I’ve got the table working and I’ve been having fun cutting roadrunners,

but now it is time to move on to bigger and better things, (and have the table help to make some money).

Now to my question to you sages of the milling world:
Since I will be milling Guitar necks, Mandolin top plates, electric Guitar bodies and various other similar parts, I need to know what I should do as far as CAD/CAM software. Of course I am looking for the Holy Grail here; a really cheap (or free) program that is quick to learn and very easy to use, that will do 3D. My operation is very small and resources are very limited. Do you all have any recommendations?