I use a Google search tool to monitor blogs for the keywords "house church" and find interesting things that way. Here's part of a longer post from a HC in Columbus that has multiplied once, and doubled in size just because of a change in venue.
Our house church has been meeting at our house for almost two years now. We've had a great time, we've grown, even divided/multiplied and commissioned one couple to keep planting house churches in their neighborhood. All very good things. Then just in the past two weeks we had a few things happen that seem to be showing us that we need to move on, move out to where God is working.
Luis and Laura are a sweet couple from Ecuador who are friends of Maria's that she invited to come to our house church. They have been coming for about the past three months, to our house. Then a little over a month ago they had a baby and since it is cold, they don't want to take their baby out any more than they have to. So we had church at their house a few weeks ago. Then this past week we asked them if we could just start meeting at their place every week so they wouldn't have to take their newborn out in the frigid weather. They also mentioned that they had some neighbors that might want to come to the meeting. Well when we met on Friday evening, their neighbors not only came but they brought two other families with them! So, our house church practically doubled in size in one night! The one couple came specifically because their 5 month old daughter has a blood infection and they wanted us to pray for her. (Which we gladly did!) Keep praying with us that she is healed completely.
I've been reading about how if we want to start a church planting movement we have to get out on other people's turf and the new disciples will bring others to follow Jesus as well. Now we're seeing it get started.