There are almost always two photographers roaming the walkway between Future World and World Showcase in Epcot.
There are always several photographers at all four park gates in the morning, as well as those inside that have already been mentioned.
There were two photographers outside Donald's Breakfast-osaurus when I ate there in December.
I seem to recall seeing another one roaming the midway area in Dinoland USA.
I've seen them sometimes at or near character greeting spots in MK, on the paths to Adventureland outside Aloha Isle and the path to Liberty Square, but these are rovers who are not always there.
Once in a while I've seen one in the large empty area between Star Tours, Backlot Express, and the bathrooms.
I don't rightly recall ever seeing them in World Showcase, which is odd considering how many beautiful photo spots there are in WS.