Giant windmills

One thing that we saw a lot of over in Germany were the windmills. They seem to be everywhere. Hubby and I have been talking for years about doing something similar, of course, nothing that huge! We also want to put solar panels on our home. I think that if we can do it, even though it would be expensive at first, that it would really be beneficial in the long run. Do any of you have solar panels or small windmills? Were these something that you built yourself or bought?