The single point connection was $3 billion and the three point connection(with Houston being the third point) was $7 billion.
As for the cost of the windmills, those are the cost of the generator and are paid for/amoritized in his selling price.
I'm not sure what you mean by controls except to say that these would be included in the cost attributed to the wind farm operator, the transmission line builders, or the local provider, which, in the case of the two point connection, was Oncor.
I would like to see a comparison of system costs with and without wind capacity. Wind power incurs substantial incremental costs for transmission and backup capacity. In addition, wind power has very low reliability especially for peak demand.
If not for massive mandates and subsidies, investors would not touch wind power in most situations. I have no problem with investors building any type of energy production as long as they bear the consequences for poor decisions. Political control of energy production means that politicians can spend taxpayer money on favored energy production without any consequences except perhaps losing elections.