I had a class in the beginning that I knew autocad, but all the rest was selfstudy, the only things I knew when I started learning the program by myself was the programing rules (incremental, polar and absolute programing)
So:
Incrimental (the next point is that far in X, Y and Z from the start): @10,10,5
polar (angular programing given in radius and angle): 10<150 (a line 10 long and undser an angle of 150deg.
Absolute (from the zero point of the page) 10,10,10.
I think the best way to learn a program like autocad is by yourself, I did it aloms completly by myself and went up to the level that programs like Inventor become quite easy to learn.
But some lessons for a start are handy.