I read that Durham has produced over 60 England internationals! We've produced 18 as have Newcastle. Don't know how reliable it is as it doesn't list the players http://www.chroniclelive.co.uk/sport/football/football-news/produced-most-england-players-6320449
I was thinking of Ross Barkley mate, but the original impetus for the post was just how many players have come from Liverpool and played for England in recent years. Not that I have any connections with the place , apart from seeing the Beatles at the Empire.
Leighton Baines, Steven Gerrard, Wayne Rooney, Ross Barkley and Rickie Lambert were all born in Liverpool. Sterling wasn't but John Flanaghan (who was in the squad for the current friendlies) was. You can add a stackload from the past 20 years though which sadly totally dwarfs the contribution from our cities.
Mersyside (Liverpool and surrounding areas) have produced 56 England Internationals. Tyne and Wear have produced 36 England internationals.