Follow along with five videos about life without the internet in rural North Carolina towns. in 2007, about 30% of rural NC was without internet. Unfortunately, there hasn't been an update, but it's still a powerful case study
One aspect of the digital divide includes urban-rural connectivity disparity. Jessamyn West is a rural librarian and advocate of bridging the urban-rural digital divide. The above link is to the audio recording of Jessamyn's facilitation of the "Offline America" session at last year's SXSW (South by Southwest) conference. You can get the lecture notes, slides and more here: http://librarian.net/talks/sxsw2011/.