ToT is in the Hollywood Pictures Backlot just south of the Hyperion Theater and east of the Animation Building.
It is almost impossible to miss as it is so tall. In addition, some are speculating that the line will wind all the way back to the Sun Court, and possibly beyond (anyone remember lines going back half-way down Main Street after the opening of Indy?).
As for if it will more evenly distribute the crowds, there is no way to be certain, I would guess that more APs and ParkHoppers will spend time in line for ToT, but then most will head back over to DL (of course this is all my random speculation with no bassis on any fact or experiance). There may be an increase in one-day admissions to DCA (that is what the Suits would like), but personally I don't see the one additional E-Ticket as full justification for the $49.75 (but again, that's just me).