you can check out airlines on line... whihc is often cheaper and more convenient than going to airlines offices.. although there are many in nanjing xi lu. also view these 2 sites... though it helps if u have their respective membership cards as u can get discounts...
www.elong.com or
www.ctrip.com the first being able to both both quote and book airline tickets online in real time, the other you need to email.
hope this helps... don't know of any 'agents' in pudong w english ability.