When I visited the Skyscraper Museum in February, I pored over a couple of books on NYC architecture. One of them was "Changing New York" by Berenice Abbott and the other, which I ended up buying was "New York Changing" (a fascinating series of "before and after" photographs - the first set taken in the 30's by Ms Abbot and the second set taken by Douglas Levere at the end of the 20th Century). Wonderful as my book is, I regretted not buying them both.
For anyone interested in how the city looked between the wars, this is fascinating stuff! There is also a load more interesting stuff on the site if you take the time to explore.