Hi!
I have a site site.ru, which has a big list of users from each city, and I want to make it regional by each city in Russia:
- for people who search in Google from Moscow, they will see a Moscow version of my site with CB users from Moscow;
- for people from Saint-Petersbourg - a St.Petersbourg version of my site with CB users from St.Petersbourg;
- for people from Tula - a Tula version of my site with CB users from Tula;
etc.
How to implement that? I think there must be a module, that let us choose our city (but the city must be chosen automatically), and second thing - there must be a way in CB to make in sort, that people from Tula will see CB users only from Tula.

Give some advises please, and if possible the name of the modules I need.

PS: I would like to get an answer for:
a) version of my site.ru without sub-domains
b) version with sub-domains, like moscow.site.ru, st-petersbourg.site.ru, tula.site.ru, etc.

Thank's.