I need to know any research that exists about how many church web
sites are in North America, and what affects the decision of a
non-member of that church to check out any of those web sites.

I'm attempting to discover whether or not the church web site actually
makes a quantifiable difference for the church's presence in the
community, or is it merely a good thing for current members to see
what'a going on?

In other words, is a church web site a viable form of marketing?
Statistics are very important to this piece of research.

I've checked the Barna group, but was unsuccessful.

Thanks for your help.