If you send international shipments, here is a web site that you can use to track them. It can be especially useful for international shipments made through USPS where often (but not always) you can get continued tracking from the carrier to which USPS handed off your item for delivery in another country.
You can track shipments through a large number of carriers to around 135 countries. If you use USPS, you would enter tracking information in the Post/EMS(with USPS) box.
A good site to bookmark. Also, FYI, this is one of the sites that PayPal and eBay use to research non-delivery disputes.
