I have deployed a data model in MySQL that captures this information. It's not as complex or time consuming as you first think
It was set up for an e-commerce site and has approximately 250 destinations (countries). The destinations were broadly based on postal destinations the local post offcie could deliver to. I think the data capture took around 1 day.
The associations to the postal rates (ie parvel weight, size etc a great deal longer).
Well I started off with a telephone directory which listed all the countries, realted those to continents. Also I referred to the local post offices publications on country's they served.
Have a try, if you still have problems come back to me.
One thing I did do was define continents slightly differently than Africa, Asia, Europe, North & South America. Americas were split between North, Central & South. Asia was subdivided into Asia & Australia, New Zealand and Pacific Islands.
Thanks for the tip. I already tested the database you recommended. I really don't know why i should pay 90 euro when you can get almost the same for 30 euro. I have already brought the one from Countrydatabase and i works quit nice - it saved me for at least 30hours of work.