Fighting "Civic Smallpox': The Civic Club of Allegheny County's Campaign for Billboard Regulation, 1896-1917, by Kristin Szylvian Bailey. Western Pennsylvania Historical Magazine, Vol. 70, No. 1 (Jan. 1987)
For something more recent, if not from here, this is interesting: The Economics of San Antonio’s Digital Billboard Ordinance.
update: speaking of billboards.. The mysterious Shrinkulate billboard has finally been moved. I guess we will never know what that was all about.