"Grandma spoke low german dialect and that is cohesive with this region"
low german is spoken in Germany´s north. http://en.wikipedia.org/wiki/Low_German
austrian dialects have another orgin!http://en.wikipedia.org/wiki/Austrian_German#Dialects
Upper-Austria has many of the church-books online: http://matricula-online.eu/
Zu den Matrikelbüchern ...
AT Österreich / Austria
AT-OOeLA Oberösterr. Landesarchiv
take place in list A-Z