Here's some sample links on building your own wind turbine. They're currently unsorted; what's needed is analysis, in particular, whether there are any designs that can be used by RepRap.
Collection of links from otherpower.com. One of them -- "All-Wooden Wind Generator" -- gives step-by-step instructions on building a generator from magnets, copper wire, wood, dirt (!), and a steel shaft.
Note: does have motor and other electrical parts listed - may still need to buy these
Again, needs a generator - they suggest from a broken Fisher
Einfälle-statt-Abfälle.de a translation cloud be: "Ideas out of scrap" A German Publischer for "Hippie-Life-Hacks" also has very good books abaut windgereators. I conntact them how about translations and copyrights and will try to update as soon as possible