Please, can somebody tell me where I can find the following:

Rates of Corporation Tax:
Federal
Cantonal
Comune (Municipal)

Template/Computation for Calaculation:
i.e. I understand that Comune Tax is calculated after deduction of Federal tax etc etc.

Negotiating Swiss Corporation Tax Rates
I still do not understand that one can negotiate lower rates of Corporation Tax with your Canton and Comune but just can't find anything on this.
Do I just walk into the tax office and tell them I have a company in the UK making X and would be paying Corporation Tax in total at 30%; what can you do for me?