countries

This might sound like a basic question but for someone new it seem important so I will ask it. Should I target specific countries for my internet marketing or is it better to not focus on and kind of specific locations?

I have been going through some of my records for the last several months and have noticed that over 75% of my customers come from three countries consistently. They are the US, UK and India in that order. I have always had a narrow reach as far as customers and I was curious as to if others...