Commission Report, it has whole chapters about events before 1998.
Chapter 3 begins:
COUNTERTERRORISM EVOLVES
In chapter 2, we described the growth of a new kind of terrorism, and a new terrorist organization—especially from 1988 to 1998, when Usama Bin Ladin declared war and organized the bombing of two U.S. embassies. In this chapter, we trace the parallel evolution of government efforts to counter terrorism by Islamic extremists against the United States.
We mention many personalities in this report. As in any study of the U.S. government, some of the most important characters are institutions.We will introduce various agencies, and how they adapted to a new kind of terrorism.
3.1 FROM THE OLD TERRORISM TO THE NEW: THE FIRST WORLD TRADE CENTER BOMBING
At 18 minutes after noon on February 26,1993,a huge bomb went off beneath the two towers of the World Trade Center.This was not a suicide attack.The terrorists parked a truck bomb with a timing device on Level B-2 of the under-ground garage, then departed.
The whole report is here:
http://www.gpoaccess.gov/911/index.html