The FBI quickly found McVeigh and found traces on the bomb on his clothing and a business card that read:T&T @ $5/stick, need more. The FBI believe that his extremist ideologies and the death of his wife and child 2 years earlier at Waco led to his bombing of the building. The FBI also discovered Terry Nichols helped build the bomb and Michael Fortier knew about the bombing. McVeigh was tried and given the death penalty. http://en.wikipedia.org/wiki/Timothy_McVeigh