I did a quick search and saw quite a few online plans...if you've bought one please let me know if the plans were easy to follow or not.
My grandfather used to make wooden wind driven whirligigs in the 50's but we do not have any of his.
My uncle found an old one (a man sawing) and fixed it up...now the kids want to build one.
I was thinking of a simple woodpecker design. (I remember my grandparents having one like that.)
My son was also thinking of making one from found items, not necessarily wood.
So...if you've made one...is it really difficult? Want to share photos?