Definition
I've always understood the term "mechanical inspiration" to be synonymous with inerrancy, although I believe technically that mechanical inspiration refers to God's ensuring that humans wrote what God said to write and inerrancy that the autographa were themselves without error.
In neither case would printer's mistakes like The Adulterers Bible be covered by mechanical inspiration.
Modern Adherents
Much of the Southern Baptist Convention (especially say, the Texas General Convention) and most "Bible Church" evangelicals believe in inerrancy.
This issue, of course, is what divides Baptists more than anything else. The more conservative conventions (Texas, Alabama, Georgia) tend to make this a litmus test. Paige Patterson (I've had him over dinner!) would be one such leader of this line of thinking.
History
As recently as the 1950's, the Lutheran church also accepted this position.
Rogers' and McKim's classic work The Authority and Inspiration of the Bible (1979) argues that it is a fundamentalist and evangelical novelty, although Paul Achtemeier's book The Authority and Inspiration of Scripture (1995 - I think?) would argue this has been the historical position of the church.
The classic source and defense for inerrancy is Francis Turretin, who expounded this doctrine as an extension of his understanding of Calvinism.