Do anyone know how to track location details(country / Region / City / IP Address) of sitecore anonymous user?
You need to setup Sitecore Geo IP location: https://doc.sitecore.net/sitecore_experience_platform/setting_up__maintaining/ip_geolocation/setting_up_sitecore_ip_geolocation
The Sitecore IP Geolocation service provides information about the location and owner of an IP address beyond that provided by a reverse DNS lookup. IP Geolocation information includes the country, state, city, and the registered company name of every visitor.
The Sitecore IP Geolocation module is included in Sitecore XP 8.1 by default, so you only need to subscribe to the Sitecore IP Geolocation service.