Lots of info on this technique. Nip onto Google and search for "Klink and Dink".
or "New Zealand method dry fly"
There are a few folk on here that are far better than me at this method, but the buzzer/nymph is indeed fished "after" the dry fly so it hangs pretty much under the fly (depending on current).
Either attach the dry direct to the end of the leader then add an 18" to 24" length of line tied directly to the bend of the dry fly, and add a nymph on the end..or, as you say, fish the dry on a dropper.
Some stuff on YouTube as well.
Hope that helps a bit