I too am just getting into PCB milling. I found
www.millpcbs.com to get a nice starting point with some of the basics laid out. As far as tutorials, I haven't found any. Right now I'm upgrading my mill with a high speed spindle. I have a CNC converted X2 mini mill, but if all you need/want to do is mill PCBs or engrave/etch then a gantry router with a high speed spindle should work.
For the software, you can use Eagle Cad. This will allow you to draw and layout your circuits. Then you can export to gcode with pcb-gcode for Eagle. On the other hand, if you are using pictures of circuits (like from magazines) then you may want something like VCarve to be able to vectorize and create your G-code.
I'll share as I learn more.
FWIW,
Jay