Much depends on how large or important your city is for how easy or difficult it will be to find information about a city. Encyclopedia Britannica and CREDO Reference -- and others, see the tab for Encyclopedias and Almanacs, above -- are good for basic information for just about all cities.
List of Cities - Wikipedia has starting points for many sources of information on a particular city grouped in different ways.
CityLab News stories and maps. "CityLab is committed to telling the story of the world’s cities: how they work, the challenges they face, and the solutions they need."
Most city governments have a department or office dedicated to business or economic development with a web site that will point you to data and statistics on what is best about a city. Search Google for your city and the phrase "economic development" or "business development". For example Chicago and economic development (The office for the city of Philadelphia uses the term "Commerce".)