A while back I make a home made wind generator from a desk chair, a ceiling fan, a treadmill motor and some bits from the hardware store.
A treadmill motor makes a great generator, due to the fact that it uses permanent magnets to create enough force to push a person. When you reverse this, the magnets create a current in the wire and can slowly charge a battery. A solar controller is used to ensure that the power from the battery only flows one way, if not the propeller would just run on the current connected to the battery. Finally, a deep cycle battery is needed for charging. Your average car battery is only supposed to carry enough current to start up your car and maybe run your lights and radio for a little bit while you are waiting. You will notice that even though your dome light may be a small light, it is enough to drain your battery overnight. A deep cycle battery can withstand frequent charging and discharging, and are typically used on boats or power scooters.
The largest drawback to this project was that I had difficulty raising the fan to a safe height, and ultimately needed to relocate the generator to a more remote location where the spinning blades would not be a danger.
For a more detailed step by step guide, check out this very useful and detailed tutorial: http://www.mdpub.com/Wind_Turbine/