Here is a list of some of the books Kathi and I have been reading on this subject. Clicking on the title will take you to an Amazon page. The books are not in order of preference, just in order of how we read them.

The Church Comes Home  by Robert J. Banks and Julia Banks (Jan 1, 1998). Lots of great stories, fairly practical.
The Global House Church Movement  by Rad Zdero (April 2004). Excellent philosophy of the movement.
House Church Manual   by William Tenny-Brittian and Bill Easum (Paperback - Jul 2004).  Very practical, how to take up offerings, etc.
Houses that Change the World  by Wolfgang Simson (Mar 6, 2001). One of the most important philosophy books.
The Shaping of Things to Come: Innovation and Mission for the 21 Century Church by Michael Frost & Alan Hirsch (Nov, 2003). Extremely good, a bit technical, shows how to reach people where they are, not waiting for them to come to us.
The Forgotten Ways: Reactivating the Missional Church  by Alan Hirsch (Jan 1, 2007). Possibly better than his first book (Shaping), with many great examples.
So You Want to Start a House Church?: First-Century Styled Church Planting For Today  by Frank Viola (Sep 2003). Practical, lots of teaching on how to get started.
Who is Your Covering?: A Fresh Look at Leadership, Authority, and Accountability  by Frank Viola (Jan 2001). Interesting way to deal with some of the issues about leadership in house churches.
When You Come Together by Felicity Dale (DVD—available from www.House2house.tv). Lots of good examples, but of course looking very American.
The House2House magazine is about house churching and has some pretty practical advice in almost every issue.
The Present Future: Six Tough Questions for the Church by Reggie McNeal (Oct 3, 2003). Top-knotch questions and answers about what is happening in the institutional church.