Are you trying to map and height map on a sphere without pinch distortion? Like needing Equirectangular height maps?

If so, there's this plugin for PS - Spherical Mapping Corrector by Richard Rosenman ( or at his website here )

You can also use panoramic photography tools which I've used before as a PS plugin to convert for cube maps for video games, which also converts different types of maps - but cant find the link atm.

there's also this Fixing your equirectangular poles

hope it helps