Most MODIS Land products use the Sinusoidal grid tiling system. Tiles are 10 degrees by 10 degrees at the equator. The tile coordinate system starts at (0,0) (horizontal tile number, vertical tile number) in the upper left corner and proceeds right (horizontal) and downward (vertical). The tile in the bottom right corner is (35,17).
As a service, we provide above maps as SHAPE file to easily identify MODIS tile numbers for a certain region (tile numbers are stored in the attribute table):