You won't find SWTOR on Steam, D2D, or any other digital download service. Apparently, it will be exclusively sold online via Origin, EA's upcoming digital distribution service for EA games. Physical copies will still be available at the usual retailers though.
In an interview with Electronic Arts CEO John Riccitiello, the Wall Street Journal reports (subscription required to view) Star Wars: The Old Republic will exclusively be a part of their new digital delivery service named Origin. EA will announce more details about Origin tomorrow (Friday).