It is easy to white label or launch a hosted directory of local businesses; there are countless providers who can even segment the directory to a specific locality or category (i.e. restaurants, plumbers)
How though would I go about getting a hosted directory of a specific niche within those categories? Say I want a directory of Italian restaurants or barbers but not hair salons. How would you get one?
Is there anyone who can support a global directory and not just U.S.?
I'd look into pulling from the Google API. I'm not sure it supports categories, but it's worth looking into. You might need someone tech-savvy to do this, but it'll help you grow quickly without having to do a lot of data entry. I've talked with a startup that does something like this for restaurants and I think they pull their data from somewhere. I asked them now, I'll let you know when they get back to me.