I wonder if there's a book on the history of the various movements that somehow came together to form modern day Salafiyyah (i.e. Wahabism, Egyptian neo-Mu`tazilism, Ahle Hadith, etc.) and how they eventually coalesced into what we know and see today. I think it's interesting, and unfortunately something that doesn't get a lot of attention. While tackling their doctrinal positions and refuting them is one tactic, and it works, it may benefit to present a fair history of the movement, to show how it came to separate itself from the rest of Ahlus Sunnah.