Archives.com has just posted my article, "Ten Little Known Indiana Records," but the truth is that these sources are little-known, and underused, everywhere! My examples come from the Hoosier State but most of these records exist elsewhere. If I were rewriting that article today I would probably shoehorn in a mention of "local laws" from the 19th century as another example.
Genealogy learning is a constant alternation between learning about new (to us) sources, and learning new ways to use them (methodology). We need to keep doing both in order to keep growing.
Harold Henderson, "Little Known Indiana Records," Archives.com (http://www.archives.com/experts/henderson-harold/indiana-records.html : accessed 26 July 2012).
Harold Henderson, "Get Out of That Rut!," Midwestern Microhistory: A Genealogy Blog, posted 27 July 2012 (http://midwesternmicrohistory.blogspot.com : accessed [access date]). [Please feel free to link to the specific post if you prefer.]