Artificial composite materials have found their way in many applications, notably in aeronautics, and they increasingly require non-destructive testing for better design, use or control. Yet they exhibit complex electromagnetic behaviors, due to anisotropies and multi-layered geometries, and the computation of the dyadic Green's functions as is needed to get their response to a given excitation (from kHz to microwaves and beyond, depending upon conductivities of the materials involved) is challenging. A novel scheme of computation dedicated to planar-layered structures with (mostly) uniaxial anisotropy, ensuring good accuracy and saving computer resources in the computation of these functions, is considered herein. The work is illustrated by examples from eddy current to high frequency cases for a variety of illuminations, geometries and material parameters.