Starting with a satellite view of the city from Google maps I'm using SketchUp to model the buildings . I made a screenshot of the city and imported the .jpg into SketchUp. From there I can outline the base of the buildings and pull the model up out of the outline. I am referencing skyscraperpage.com for building heights, then using Google maps and Bing maps satellite and street views to get details for the buildings.
I spent about 8 hours on the first building, the Westin hotel and then about 6 hours on the new Regions Bank building next to it. Later I spent about 7 hours on the Duke Energy Center building, where I work. Next to it is the Mint Museum, and Museum Tower apartment buildings which took me another 6 hours. I then decided to tackle One Wells Fargo Center which took me about 14 hours. What made it so difficult was that it is about 1 degree off of the X-Y axis in Sketchup and I didn't realize that one of the walls was automatically snapped to the green axis. When I got to the top of the building, it wasn't symmetrical, so I basically had to tear it all down, find the stray line and rebuild it all.
Although it isn't a skyscraper, the Bank Of America stadium is a significant landmark in the city that I want to include in my model. For this, I got a very zoomed in satellite image to base it on. When I tried outlining the building in SketchUp, I found that my lines were not staying on top of the picture, which meant I couldn't see where one line ended to connect the next line. Not knowing what to do, I "exploded" the .jpg image of the stadium and then my lines layed on top of it just fine. I was in for a real surprise when I pulled the building up from the base because the image remained on the extrusion. I was not expecting this at all. I thought the extrusion would simply be the basic white material in SketchUp. Then when I started manipulating the surfaces , I found that the image stuck to those too. The result of 7 hours of design work was this really cool looking model below, which took about an hour to print