Place a basic generic model family repeatedly at the points which you want, then get all the family instances with an all elements of family type node. Then use an Element.Location node you get the points you places them at. Point.X, Point.Y and Point.Z will give you the coordinates. Now just wrote to excel.
Note that you may need to change the values to the project coordinate system and report those values.
Leveraging a coordinate system annotation may prevent the need to change coordinate systems (by reading the coordinate values instead of the location) but when I had to do this (several years back) I personally find those harder to hit the exact locations I wanted.