Per the FAA:
Shallow - less than 8 degrees
Normal - 8 to 12 degrees
Steep - more than 12 degrees (with 15 degrees being the recommended maximum)
As far as what it looks like, remember that the "spot on the windscreen" technique only works to identify the place where you start your descent. As you decelerate, the aircraft attitude changes (more nose-high), so the spot will "move down" even though the angle remains the same.