My view of punishment for sin has always been that there isn't any -- there are simply consequences to the choices we make, some of which might be natural consequences that occur in this life and some which might be eternal consequences that are imposed at the final judgement.
There seem to plenty of examples, however, of God punishing people on earth during their mortal lives for sin (Korihor, Sodom and Gomorrah, the Nephite/Lamanite cities at Christ's coming, the flood).
Do you think sin ever brings misfortune in this life as a punishment from God?