I have read over and over in various places about coordinate transformations, and understand the theory (really!), but can't find any worked examples of actual use of the transformation equations. Does anyone know of any web references or tutorials on the subject? To make things a little more specific, I am ultimately interested in converting between Schwarzschild <=> Gullstrand-Painleve and Boyer-Lindquist <=> Doran coordinate systems. I find it very puzzling that such an important topic does not seem to be applied in any depth in any of the books and other sources that I have. Perhaps just looking in the wrong places . . . .