My annual conference's Facebook page contained this post concerning visitors to churches, and how churches can effectively respond to them. http://seelydarun.com/2012/02/27/open-letter-to-churches-seeking-new-members/
On a side note, I've been on both sides of visitation: as a church staff person trying to fine-tune and monitor our "system" of visitation and to encourage congregational warmth toward visitors, and as a "church shopper" with my family in a new community. I get a little upset about this subject because it's such a basic aspect of ministry and so many churches screw it up---although I try to be compassionate, knowing how difficult it is to get everything in the right balance. I've a friend who isn't a church attender but would attend if she could be assured she'd not be fussed over and pressured. Some churches don't even follow up on visitors. In one community to which we moved, the first church never responded to us, the second only responded with an email request for money to an emergency fund of some sort, and after we'd visited the third church, the pastor dropped by with a small gift. We did join that church after a year or so. We were interested in another church and finally had to ask for someone to provide us information about it after our third visit.