That depends on the type of turbine, and how many you need. For example, one commercial grade turbine can cost around 3.5 million including installation. For one personal turbine to create power for one home, you're looking at about $50, 000 ... so ... do the math :)
Wind farms are costly projects: 1,000,000 USD for a typical 1,5 MW turbine. And since a wind farm involves a reasonable number of turbines, investments of more than 20,000,000 USD are common.
i was talking the big farms that only have them. not the a farm thats energy comes from wind.
That is too much.