I am a strong believer in not reinventing the wheel, and a stronger believer in using resources that others provide free of charge if its "wheel" is as good as one sold. At root, Christians make up one spiritual body and I'm not embarassed to say someone else is on a better track tham me.
To that end, I've downloaded (in PDF) and am reading three of these, and hope to have them all reviewed by year's end. They are:
The Vineyard Central House Church GuideBook by Dave Nixon and the House Churches of Vineyard Central. Copyright 2000 Vineyard Christian Fellowship -- Central. (Normally available for purchase to nonmember in print format for $10, the print version is out of stock.) [2008 May 1. Download it here.]
Getting Started: A Church Planting Handbook for Laypeople by Bradley L. Boydston. Third edition. (He's a minister in the Evangelical Covenant Church.)
A Handbook for Church Treasurers and Trustees by the Massachusetts Conference of the United Church of Christ. October 1998.