Cities, Municipalities, or Settlements?

I'm trying to build a form that lets a user enter an address as easily as possible.

The way I had it before is you would choose a country, and then a list of provinces/states is populated, you choose one of those, and then type the name of the city.

However, I think this could be made easier. A lot of apps (ex. Facebook events) allow you to just type the name of the city, and then the country/province can be inferred, so I'm trying to build something like that.

I live in BC, Canada, so I'm starting with that. Looking on Wikipedia, there are a number of "cities" that are left out, such as Delta, which is a fairly big region over here. It should probably be included in the list, because in colloquial conversations, people usually say I live in "Delta" or something, even though it's not really a city. So maybe I should actually use municipalities which seem to be a superset of the cities.

But then we've left out places like Ladner, which is actually a 开发者_如何学Csub-region of Delta, but now I'm worried I'm getting too specific?

Thoughts?

Also, this is just Canada. I have to include the United States as well. I'm not sure if the states are divided up quite the same way, how fine-grained should I go there, fellow Americans?

If you were trying to get the weather, or time, or trying to look up a location, and were presented with a form, how fine-grained would you expect it to recognize?

As an American, all I usually care about is City and State. Maybe an option to omit the city and fill in County/Region like you were talking about above would be appropriate, as not everyone lives near enough to a city to really claim to be from there. The only issue is you'd have to keep track of all of these in your database, and keep them updated. I'm not really sure how to go about that.

For the United States, check out the USPS City State File. This will never get all the common place names, but should cover most incorporated cities, townships, municipalities, etc (and a few unincorporated places as well).