I am looking for a list of towns, cities by country (the countries I mean here are all countries that exist on planet Earth). Is there any open-source SQL database available online which I can download and use, or any geography social network sites APIs I can use?
Or is it something I have to make it up myself? - I hope not!
There is a sample database for PostgreSQL with that information. I don't know how outdated it is, though...
It's hosted in http://pgfoundry.org/projects/dbsamples/.