Books about NYC

Low Life, by Luc Sante, is my favorite book about that period. It doesn't focus on yuppies, but there is a lot about their interface with New York's more seedy side.

http://www.amazon.com/Low-Life-Lures-Snares-York/dp/0679738762

not precisely the time period you're looking for but "Walker in the City" by Alfred Kazin is my favorite non-fiction about NYC.

The Alienist by Caleb Carr but it is fiction.

How to find a book on turn of the century "yuppies" when the professional/managerial class as we know it was really just getting started... That's a tough one. Interesting, and apropos too (I wonder how today's income disparity compares to that of the Progressive Era).

What aspect of the "young urban professionals" are you most interested in? Lots of info about social climbers/aspiring "new money" in fiction. For nonfiction, I'd look for info on these topics and then check the bibliographies:

** social mobility/professional class in Progressive era
** rise of advertising/history of consumerism
and if that's too Fight Club for you, I guess just focus on the development of white-collar jobs?

This also looks interesting:
http://www.amazon.com/How-York-Became-American-1890-1924/dp/0801882931/ref=sr_1_28?ie=UTF8&s=books&qid=1227124993&sr=1-28

Sorry no specific info, but you could always call the NY historical society or library: http://www.brooklynpubliclibrary.org/ask_librarian.jsp or http://www.nypl.org/questions/

If you do ask a librarian for help, I'd try before school lets out at 3 (they get deluged with kids looking for homework help). The resident history buff could maybe search nonfiction bestseller lists for you, if you ask nicely.

Good luck!