Steve McCoy has a great post on some recordings that were made at an Acts 29 conference back in 2000 or 2001. Steve originally got them from Kevin Cawley (pulling from his vast archives). Here's Kevin's post:

I consistently get emails in response to my Missional Ecclesiology readers guide asking if I'm aware of any sermons/conference lectures that treat these issues in a systematic fashion. Beyond the excellent A29 Boot Camp sessions (2005) and the (forthcoming) A29 2006 Boot Camp sessions, the only real source I'm aware of is, to my knowledge, no longer accessible on the internet. It is an old (the first?) church planting boot camp at Mars Hill. I got another email today asking the same question, and so I decided to upload these sessions in hope that others will benefit from them as I have.

The sessions below are some of the best comprehensive teaching I have heard on the theological foundation of the church and a practical implementation of a missional ecclesiology. I downloaded these sometime in late 2000 or early 2001. My guess is that they simply didn't make the transition over from Mars Hill's old .fm site. (If A29 removed these for a reason, please let me know and I'll take them down.)

Church, Gospel, & Culture part 1
Church, Gospel, & Culture part 2
Church, Gospel, & Culture part 3
Church, Gospel, & Culture part 4
Church, Gospel, & Culture part 5
Church, Gospel, & Culture part 6