A Public Involvement in Decision Making Toolkit
Back in 2000 Health Canada published an excellent resource called The Health Canada Policy Toolkit for Public Involvement in Decision Making.
It is a complete toolkit with guidelines, about 50 techniques described in concise details and with useful suggestions, and also case studies and references. I highly recommend it as a definitive reference on the various options for effective public engagement within the Canadian context. You can access other free resources in my links section.