Redirect based on Visitor Country

We have created a separate store for our customers from country X and we need to redirect all the customers coming to our old site from that particular country X to our new site created for them.

Whenever customer from country X would visit our OLD site, they would be re-directed to our new site and given an option whether they would like to stay on this website or visit the old site and their preferance would be stored for future visits.

I can figure out that it has to be done based on a geo-ip but how? Will be glad if somebody can help me on the changes we need to make in cs-cart code.

We are even open to developers sending us their qoute through PM for writing this script which could work with any geo-ip database (both free and commercial).

Also interested in something like that.