Green Roofs for Healthy Cities
Includes information about green roofs, public & private benefits, installation, and additional resources..
Public Works and Government Services of Canada manual (pdf file) includes advantages and benefits; barriers; design and construction; and more.
Green Roof Tech
This site is hosted by a private company promoting green roof technologies
but contains good information on the technology and on various examples
where it has been used, including some good photos of examples.