If, I were thinking about building a windmill, I would begin with this website:
www.poorman'sguides.com/index1.htm
This website opens with a spinning windmill and pictures of windmills, you can click, and view in action. The website is a guide to wind power and battery systems. The gentleman who runs the site has built windmills for various reasons and shares his experience and knowledge through an E-book, and the site itself.
The e-book, which you can purchase through his site, and then download to your computer or to a disc is packed with information, diagrams, directions and more. He shows you how to make free windmill blades, gives you a page of equations to use so your windmill, will do what you want it do.
He explains the types of generators, charging batteries, making a 1000 watt windmill turbine for less than $150.00. You can also get help, advice and communicate with him about windmills get additional information as you build your own windmill.
Another site is
www.fuellesspower.com/windmills2.htm
A site where you can purchase complete plans for building a windmill. You can charge a 12volt dc marine battery and build a 2000-500 watt inverter. The plans for this windmill tell how you can provide energy for your use, and sell access energy to others in your area. You can run your lights, TV's VCR's, DVD's and much more. Many people are building their own windmills today and selling energy to others as a private business.
This site
www.otherpower.com/otherpower_wind.html is a great website. Here you will find not only information, but pictures of many different types of windmills. Each windmill provides you with information, about the type and use of the windmill. This website is specific to what is being done in Colorado with windmills, because of the strong winds found there especially when the sun is not shining to provide solar power. This site also discusses how to make Solar panels for a solar windwill.