Output is a respectable 2 amps at 12 mph (18-20 volts) providing a cost effective alternative to a solar photovoltaic panels (if wind is available). The total cost of the windmill was less than $80 purchasing most items new (off-the-shelf). The two most expensive items were the permanent magnet motor (around $30) and the uv resistant round belting typically used in food processing plants to drive conveyors ($3 to $5 per foot).
The windmill does have a tail (see new photo). The frame is made from PVC pipe. It is important to use only a 24 to 27 inch rear solid axle bicycle wheel. The wheel is mounted to a PVC end cap via a hole drilled in the middle of the end cap.
The generator is a 24 volt DC permanent magnet motor. This one was surplus and used in old main frame disk drive units. DC permanent magnet motors are available through Internet surplus resources, but getting scarce. Here is a link that gives you more detail on sources and the types to look for: http://www.otherpower.com/otherpower_experiments_tapedrivemotors.html
The generator is mounted using a simple L bracket. Should be sturdy (not the typical shelf bracket) and both the motor and the bracket are secured with radiator hose clamps.
The windmill pole is electrical conduit that 1.5 inch PVC slides over. A short segment of PVC pipe is screwed into the metal conduit to create a bearing that the windmill pivots on (PVC to PVC).
The tail has to be counterweighted to balance the unit. Ted used a bunch of pennies and got it balanced perfectly. What else are they good for? :-)
I'm adding a couple of new pictures. Sorry we don't have more detailed steps with pictures. This was done some time ago.