Unitarian Universalist congregations have many similar organizational issues to those in Ethical Societies. This very complete resource is now available online.
Includes many nuts-and-bolts ideas -- from by-law suggestions, effective meetings, programming ideas, social justice and religious education resources, congregational planning and budgeting, and financial and property issues. Some sections are specific to UU congregations, but most are either applicable to an Ethical Society, or can be easily "translated."
The Congregational Handbook
How to Develop and Sustain
Your Unitarian Universalist Congregation
The UUA Congregational Handbook - Table of Contents