Im chiptuning fanatic. I would like to share some information to help you learn. I will write about tools available on market, finding maps, switches in WinOls. Mainly TDI engines. I will try to write as much as i can.
I have seen that many people call them as chiptuners and they files were worst in world. So if you are IT guy or intrested in it would be really easy for you to do it yourself. But remember bad tuning can lead you to killed turbos, engines. If you are not sure about what you are doing ask some professionals or continue reading.