Computer Aided Design (CAD), Computer Aided Manufacturing (CAM) and Computer Numerical Control (CNC) technologies in a small shop commercial setting where these technologies are not currently in use. The focus here is on lutherie shops but the advice pretty much applies to any small shop in any field. Since, in my observation, not everyone is able to effectively deal with these technologies (at least as they are presented at the current time) the approach outlined phases in these technologies one at a time. This makes the learning more straight forward and reduces the risk of wasting money.

CAD, CAM, and CNC are highly technical tools.  In my observation folks with technological backgrounds tend to latch on to these pretty well, other folks have to really hit the books to get to where they have an understanding of these technologies, while still others just don't get it no matter how much effort they put into it. This will assuredly change with time as these technologies mature, but for now this seems to be how it breaks down.

Based on these observations I think the fastest and most cost effective approach is to buy and learn how to use AutoCAD before you do anything else.  In the past I have recommended IntelliCAD, an AutoCAD look-alike that is a lot cheaper, but my recent trials of this product indicate that the quality of the product varies greatly depending on where you buy it. From some vendors it is far too buggy to be usable. Plus, the sales organizations of those vendors don't seem to feel that getting the thing fixed is much of a priority. And there are a number of other CAD packages as well, and each has its adherents. They all probably work just fine, but all CAM software is guaranteed to work with AutoCAD and is not likely to be guaranteed to work with any other CAD package (when in doubt, ask the CAM software manufacturer). So, unfortunately, that leaves AutoCAD as the only real choice in this area. In my opinion, learning any other CAD package is not an option. You will spend a tremendous amount of time learning how to use CAD software and it only makes sense to learn the package which (for better or worse) is the de facto industry standard.  When I say learn how to use AutoCAD, what I mean is to get proficient enough with it that you can make any kind of 2D drawing with it faster than you could do the equivalent drawing on paper. I want to make it clear here that I am no fan of AutoCAD - it is way too expensive, carries a lot of backward compatibility baggage due to its age, and its user interface is arcane. But as mentioned it is the de facto standard 2D CAD package.

Once you master AutoCAD for 2D drawings, the details of CAM software and CNC machines seem to come a lot easier, so it would be prudent to make purchases in these areas only then.  Or, with CAD drawings in hand, you can shop out the CNC work.  You may find this option is preferable and it may even be cheaper.  If you never get the hang of the CAD software then at least you are only out a little money, compared to what you might have spent by jumping in with both feet, buying CAD and CAM software and an expensive machine. There is no de facto standard CAM program, but a lot of folks in the woodworking industries in general and in lutherie in particular use Mastercam.

There are no de facto standard CNC machines. Folks in the lutherie business use everything from small desktop CNC mills to large CNC routers depending on the application. A discussion on selection of a CNC machine is outside the scope of this small article.

If you follow this plan and get to where you are using all of these technologies, the final step I would recommend is to buy parametric solid modeling CAD software such as SolidWorks for your true 3D (necks, arched tops) drawing work.  3D drawing with AC and its ilk is tedious, and changes to 3D drawings are even more so.  Parametric solid modeling software makes all 3D design a whole lot easier. I have recently been using a great PSM package called Alibre Design from Alibre. It is facile, very easy to learn and use, has great technical support, and is substantially less expensive than other software of this class.

For a very detailed discussion of CAD and lutherie, check out Dana Bourgeois' great CAD articles in American Lutherie.