So has anyone ever been to the edge of the Earth and reported back?
Kartographer,
There is no edge (drop off) to the earth (as imagined by the mockers).
There IS an ice wall at Antarctica. However, Antarctica is NOT a continent. It is merely the first land we encounter as we travel south.
My understanding is that we are on a large plane (flat surface). The earth is a circular region on that plane.
Byrd explored that edge and beyond more that a half century ago. He even spoke about it on television.