help please. I have just built a small cnc machine frame. this for an engraving machine

This is a small machine for engraving pens and tool/cutlery handles . It has a z axis to raise and lower the tool/cutter. the z axis tranverses in the usual manner. The third axis is ratary spinning the workpieces. I need good accurancy so what is best in terms of motors I have many motors liberated from printers scanners etc and access to new motors at reasonable price including 200 and 400 step per rotation . Is an arduino suitable for this or should i go for more mainstream breakout driver boards? I have mach3 Cad std Inkscape image to cad  etc

Make sure you have a good stepper motor with as many steps as possible. You may have to try a couple of motors till you find the one that works best for you in both holding strength and number of steps. Keep in mind if the motor you choose isn't strong enough for you or doesn't move in small enough steps you can always gear it down.

For the brains of the system Arduinos are used to run much more complex systems. Many of the main stream driver boards used in 3D printers and DIY CNC mills need an arduino or other micro controller to run them.