An easier method than creating a star map is to use the brightest star in the sky (the sun) and an accelerometer. This is the method Opportunity uses to calibrate the gyroscopes/wheel encoders.

[source pg 4] https://www-robotics.jpl.nasa.gov/publications/Reg_Willson/M...

"The attitude of the rover is based on measurements from two vector instruments: (1) accelerometers that determine the vector towards the center of gravity of Mars and (2) Pancam solar images that determine the vector to the Sun."

Star maps can be downloaded free.

Because you generally only need the brightest subset of stars in any area, you don't even need a comprehensive one.

A star map for Mars would functionally be pretty much equivalent to an earth one, I guess, given the distances involved.

The stars would be the same, of course. Out of curiosity, I launched Stellarium, moved to Mars, set myself at 90° latitude north, and watched directly overhead. Mars north pole seems to be aligned halfway between Cygnus and Perseus, so there is no "North Star" equivalent on Mars.