You can send to him c/o the Baltimore Ravens. The address should be in the database. You can always send to an active player, coach, or executive c/o their respective team. You may have to wait until the regular season to send to Michael Oher, unless you can find a training camp address for the Ravens, as not every team forwards mail during the offseason, and who knows if they hold it during the offseason.

this might not be the right place since he was a NFL player but does anyone know where to write to him?