You should read about the hypershade in the manuals..
Look at the grid texture, combine it with some noise or a fractal shader, adjust the colors and intensity, maybe apply some ramps and stuff - and perhaps add some color adjustment nodes and you will soon learn that Imagines procedural shaders are babies compared to the possibilites with maya's procedural shaders.
But all hypershade and texture/shader generation is explained in the manuals.
Good luck - and let us see what you come up with
Carsten Lind
Senior 3D Artist,
Maya Software Manager & Maya Instructor
LEGO Systems A/S