That's a tough one--it looks sort of Art Deco. It can be very hard to find matches for specific buildings. "Downtown Deco" might have something similar. This one doesn't look too hard to create, though: you could use prefab windows from any number of companies, and the walls are very smooth stucco so .040" or .060" styrene would be perfectly suitable. Just cut out window holes, add a strip of styrene below each window opening, and install prefab windows. The decorative molding along the roof line is a little more difficult: I'd say take a clear photo on actual film and scan it and resize it to the model's size. Print it out and you have a pattern to use for cutting out styrene to fit the model. It is unclear whether the decorative touches above the windows are tile or paint, but printing them out on an inkjet printer onto thin paper and gluing them gently in place above the windows (after painting the building) should produce a good result. The decorative moldings in between the windows are a bit more of a challenge: personally, I'd print them out too, and mount them on a piece of thin styrene with the sides painted dark gray, to suggest a 3-D effect without having to actually model the darn things, especially in N scale. If I wanted a real challenge, I'd suggest making a tiny copy of the moldings in Fimo clay, baking it, and using some liquid latex to make a mold, then crank out a bunch of those things in plaster or other material.
If you haven't tried scratchbuilding, this looks like a really good starter project: the building has very simple lines (basically a box) and the smooth surfaces means that you don't have to mess around with brick or wood patterns.