Ibn Abd Al-Wahhab, Muhammed 
Biography (1703-1792); also includes an account of his later influence. Article on Wikipedia.
http://en.wikipedia.org/wiki/Muhammad_ibn_Abd_al_WahhabImaam Muhammad Ibn Abdul Wahhab - His Life and Mission
A biographical article by Shaikh Abdul Aziz Ibn Abdullah Ibn Baz.
http://www.ahya.org/amm/modules.php?name=Sections&op=viewarticle&artid=180
Kitaab At-Tawheed
Ibn Abd al Wahhab's "The Book of Tawheed" - translated as an online book by Sameh Strauch.
http://islamicweb.com/beliefs/creed/abdulwahab/
