As shown in Appendix B, the debris for each building was found within and near the footprints and was pushed, or fanned outwards from the 4 exterior walls.
If we ignore WTC7 and consider only debris from WTC1 and 2, all debris exists in 8 natural regions as shown below.
Southward from WTC1 and westward from WTC2 share a region (we'll call it "southwest complex") and eastward from WTC1 and northward from WTC2 share a region (the plaza area). Hence 8 natural regions total.
It is hoped that by rearranging all known useful debris photos by region, the reader can see for themselves how debris was distributed throughout the complex and in what condition without being overwhelmed with information.
The largest publicly available collection of debris photos are linked below: