> I'd like to know if there are any resources about the practical
> everyday use of CAD.
I think the best way to learn CAD is to customize it. If you're only reacting to tools, you're not really considering exactly what that tool is doing (and not doing) for you.
Once you begin customizing (actually developing software or at least scripts) you don't understand how the framework operates. But when you are trying to program some functionality, you quickly understand the limitation or simplicity of it.
Think of a task that would make your job easier. Then write a script to do it. Extra points if it's so easy you can explain it and let someone else use it in a sentence. Then donate your work and your advice to newbies. :)