This is just a nit for me, but how can you present a city in an article and not provide a map of said city?
To me, this makes the thing completely useless. I don't care how good your description is there is nothing that takes the place of a well drawn city map. A map says at a glance what hundreds of pages of descriptive text could only begin to scratch the surface of. A clear understanding of the layout of the city, an understanding of how the shape of the city came to be, a clear view of the city's orientation with the rest of the countryside, and so forth.
I bring this up because I have been looking through the magazines of Dragon and Dungeon trying to find useful articles to "steal" from, and while the cities described sound interesting two our to the three provided thus far have no map. Tu' Narath has the barest of a map, which shows the districts and an outline, Greywall doesn't bother, and only Tarmalune takes the time to provide a very nice color map of the place.
Are the maps in other supplements? Why not simply reproduce them in the article for convienence? I have no Eberron supplements, but that doesn't mean I wouldn't lift a city whole cloth from the setting to put in my own. No map? Forget it.
Bottom line. If you're gonna take the time to write a nice detailed article about a fantasy city, do us all a big favor an provide a map of the place for gods' sake, eh?
End rant. Thank you for your attention. 
None of the backdrops appear to be location-dependent. By this, I mean that there is nothing that indicates the distance between two described points -- or the specific location of any given point -- matters. Given this, and just in case a solution is at least a part of your objective...
Google images provides a list of 425 million city map images. Restrict it to keywords medieval city map and you still have 3.33 million. Restrict that to large ( 800x800 minimum size) images only, and there are still 24,000 images.
I have no difficulty finding city maps. Populating them with description is the hard part, and the Backdrops give me that in a way that a Google search cannot.