How to show a notification at a speicific page based on visitor's country? I need to notify (only notify) users ordering through my Drupal Commerce based website that we don't serve their country, if they are not from a specific country. How can I achieve this on the checkout page only?

I know smart IP module can help me determine the country per IP, how can I implement the notification at the checkout page, before user proceed with his order.
If you can sort out the Smart IP bid and you get the user's country then you can use Context and Context GeoIP.

Create a new Context where you can choose the countries you don't deliver as a condition and show block as a reaction. Your block might be a modal box informing your users.