How do you address holders of non-Ph.D. doctorates such as an Ed.D. or Sc.D. etc.?
Traditionally, you would also address these people as "Doctor", as the distinction into different types of PhDs is mainly a naming thing.

As an example, look at Britain. Oxford University confers "DPhil." degrees, while Cambridge University confers "Ph.D." degrees. If you look at academic web pages of lecturers of British universities, they will be listed as "Dr" regardless of where they get the DPhil or PhD from. This is the same for other variants of the PhD as well.

Note that it can be that a person with such a degree does not call himself/herself "doctor" (which can be the cause of such a confusion). This can be due to legal requirements in using the Doctoral degree as part of your name or as a prefix to it. As an example, in Germany, if you got a PhD from a US university, you will typically not put a "Dr." in front of your name, as legally, you are only allowed to do so if you got a PhD degree from an accredited institution in a country with which Germany has a contract about seeing the degrees as equivalent. It is however fine to put a ", PhD (University name)" behind your name in this case. And there is no obligation to correct somebody if he/she calls you "Doctor" if you only have such a degree.