It would cost me right at $25000 for a wind turbine to supply the energy needs of my small house. That would take a long time to recoup.
About 10-15 years? Location has everything to do with it. Its all about the mindset and long term investment, do you have $25K sitting in the bank doing nothing which you can use to shave $120+ per month off your utility bill? That $120/mo. could be applied somewhere else over the life of the windmill incerasing your rate of return.