not cranking/turning over?
with a battery and starter replaced, this is what i would think your problem is.
obviously a bit late, but those can be tested for free at most auto parts stores prior to replacing them.....
is your starter relay part of the starter or seperate?
with the year, i would think it must be in the starter, but i'm not a mitsubishi guy.....
if the starter relay isnt working, your starter isnt being told to spin the motor when you turn the key.
otherwise, i'd suspect either a clutch switch (sitck shift) or a park/nuetral switch (automatic). those prevent the starter from working in order to prevent the vehicle from moving as you try to start it.