Disclaimer, the following are my OPINIONS! I am no expert, just a craftsman trying to learn new techniques and methods.
I am working thru this issue right now. From what I can see in my internet research, (many hours) there are actually 3 kinds of software involved. (please note, I am NOT an experienced CNC user, I am purchasing an american made machine and haven't received it yet).
At any rate, first there is the software that runs the controller that drives the stepper or server motors that move the router in 3 dimensions. From what I see, the most well known is Mach3 by ArcSoft. The have a user forum here
. Again, you have lots of choices to sift thru.
Then you need a software that tells Mach3 what to do, like which tooling you are using, what depths of cut, how many passes, and lots more parameters.There are many; the Shark (sold on Rockler.com) comes with Vectric's Vcarve Pro. Another is BobCad-Cam V24. And each has different versions with different functions and different prices. You can spend days trying to determine which one you want to use.
IF you buy a complete unit (hopefully a brand name) the CNC router manufacturer will probably include software with the unit. From what I can see there are LOTS of parameters and tools in any of these types of software and each brand has a pretty steep learning curve. Pay close attention to the availability of support, as sometimes it can cost nearly as much as the software. If you decide to jump into the real
fire and want to build your first unit, be prepared to spend lots of hours on the different CNC forums learning a huge amount of new terms, techniques, and device names. Truthfully, I gave up on that idea. I'd rather spend my time woodworking.
then, there is the software to actually create a design in a format that the CAD/CAM software will import. Here the market is even larger and includes apps like AutoCad, TurboCad, SolidWorks, and Googles Sketchup (not the free version, tho, it will only export a .skp file which most CAD/CAM software won't recognize). Most will have a limited function trial software that you can download, but I found using them difficult as a beginner with no training. Some are quite expensive, have MANY functions, and are hard to learn. I seems to me that most require lots of study and practice, and their tutorials can be difficult or impossible to decipher without support and instruction.
From my perspective, and I have been woodworking for several decades, using hand and power tools. Moving into CNC routing is arduous and challenging, but I am hoping to finally be able to create my designs in quantities that make it profitable.
I hope this gives you some idea of the challenges you would face.