We'll create fresh WordPress site with Ipgp User Country Flag installed. You have 20 minutes to test the plugin after that site we'll be deleted.
The plugin will show your visitors their country flag, based on their IP Address. You can add it as a widget to your sidebar, using a shortcode in your post or pages or directly in your template trough template tags.
The geolocation is provided by http://www.ipgp.net
You can use [ipflag] shortcode, add it trough a widget, or directly into template with <?php echo ipgp_flag(); ?>