The link for the place in Berea appears to be for Homegrown Hideaways (
http://www.homegrownhideaways.org/) which does have an in-progress cob structure, but it is not complete. We visited during the 2012 Berea
Solar Home tour, and Jessa, one of the owners, showed us around. Its a great place to visit, and I'd suggest it to anyone interested in natural building, but there may be better options for seeing a finished cob building.
On the Berea college campus, there is a small structure built from various natural methods. This building has one cob wall, as well as walls made using earthbags, cordwood, and
straw bale. The building is next to the Sustainability and Environmental Studies House. I contacted them once about touring the building, but ended up just doing it during the
Solar Tour. Information on the SENS house can be found at
http://senshouse.org/.
The only completed cob home that I'm aware of in this area is located at Disputanta Cob (
http://www.disputantacob.com/) in Rockcastle County. Unfortunately I've not been able to tour this home, as the owner's ill mother is currently living there. She offered to arrange a tour for me sometime, so I suspect that she'd be willing to do the same for others. The website contains contact information. There is a small, mostly complete, cob cottage on the grounds that I was able to take a look at when I stopped by.
You might be interested in checking out a blog entry I wrote about my
experience with the 2012 Berea Solar Tour, which discusses the three structures above as well as a few other locations in Madison and Rockcastle Counties -
http://simplelivingcomplexworld.blogspot.com/2012/10/2012-berea-solar-tour.html