The wikipedia article seems quite US-centric, but for those of us in other parts of the world, there are likely to be resources available if you search, both on

The wikipedia article seems quite US-centric, but for those of us in other parts of the world, there are likely to be resources available if you search, both online and in print. My inspiration as a child was L. Hugh Newman's Create a Butterfly Garden; probably out of print these days, but it was a delight of a book for a youngster in the 70s.