Hi winny.
Wind Turbines, I can recommend Hugh Piggots, he is also in the North of Scotland.
Over the past 30 years Hugh has finely tuned his deigns so that they are simple, robust, very efficient, and easy to make. His site,
http://scoraigwind.co.uk/.
He has put all the info into a book, Called "A Wind Turbine Recipe Book" , and does several sizes up to 4.2m diameter.
My 3.7m dia Turbines keep on going in all conditions where sadly the Chinese stuff falls apart.
There is also Dan Bartmann's book "Homebrew Wind Power", this book is from USA and is written as a manual of construction with designs up to 5.2m dia (3000Watt).
However in the front of Dan's book page 17, is, "There are very few people in the world who truly deserve the title of "Genius" but Hugh Piggot is one of them, one of the very best in the area of wind technology" .
I agree.