KCM Blog has a write up on the results of the recent Google / National Association of Realtors collaboration which studied the "evolving role of digital media in the consumer home search process."
It found that 9 out of 10 home buyers relied heavily on the Internet as part of their home search.
http://www.kcmblog.com/2013/01/15/google-nars-study-on-digital-home-buying/