Many of the Congressional Pearl Harbor Hearings reports -multi-volumes - can be found there (note that many are tens of mega-bytes in size, but as these are PDF files they are conveniently searchable).
There is also an index into these volumes from the Greenwood Press - often helpful.
I suggest that you might begin with the Minority Report.
And no, the capacity of the IJN was not underestimated; the amount of damage at Pearl Harbor was by FDR and his War Cabinet, particularly Knox. The IJN ability to sustain losses and yet maintain a fighting spirit was greatly underestimated - a cultural thingy.
Same as to the IJA. The brutal fighting to the death at Guadalcanal and Papua New Guinea came as quite a shock. And we just passed the 70th anniversary of Tarawa where the Japanese very nearly did literally fight to the last man.