As many have stated, the hard truth is that the chances are extremely slim.  It sounds like the possibility of cloud storage is off the table, so the only two chances are:

1) Thief goes to Apple store for repair and it's flagged stolen
2) You physically track the individual

You had also asked if recovery is possible in the event that you recover the laptop and the drive was wiped.  While theoretically possible, realistically it's unlikely.  If the computer has never touched the hands of someone technologically capable, then perhaps it was never wiped, but obviously just finding the computer is your first hurdle.