I'm sure the collected wisdom of uk.diy can help with this. I'm making some electronics for a rather unusual sculpture which reacts to environmental conditions. One of its triggers is wind speed. I have googled for ages trying to find someone who supplies anemometer mechanisms, the 3 cup sort of thing, which will attach to a nearby building.
It does not need to be calibrated or anything, just output a pulse train which has frequency proportional to wind speed.
Maplin used to do one, but don't seem to any more. The only other ones I can find are pukka meteorological ones which cost about 500 pounds. If anyone knows a supplier for the maplin-type thing I would be most grateful. I have in the past diy'd an anemometer but the bearings proved to be problematic so I would rather buy a mechanism. I will however be doing the electronics myself!