Tables, Etc. Issue With Regions And Countries

Hello, this is my first post and should not be a difficult one as I am still a learning novice:

I am using Access 2007

My database includes a Table of "providers" located around the world. Each provider obviously has its respective address. To select the country, there is a lookup pointing to a "countries" table.

The problem is that I would also like to have a "regions" table, region being just a general well-known region such as Yucatan Peninsula in Mexico. Therefore each provider may also have a region specified in addition to just City,State,Country like Cancun,Quintana Roo,Mexico. However, the many countries may have regions with the same names, therefore this table must also depend on countries. In other words, every regionID is made up of both a country lookup from the "countries" table and a region, like "Yucatan Peninsula".

I think this is the best way to do it so far, but now I am wondering how I would fill the region info in on the Providers" table. If i have a lookup for that regions field it would show each all of the regions, but like I said there may be regions with the same names in different countries. How could I fill this in without manually entering the RegionID from its own table. Eventually I obviously want a nice form to fill this in. One thing I was thinking of is if maybe after entering the country, the regions field could automatically narrow down to only those found in that already selected country. But then we would not want people filling in the region before the country.

I hope my problem is clear, just ask if not. Thanks very much, Dillon