Drupal Commerce note: The 7.x-1.0 release will be compatible with Drupal Commerce as well as Ubercart.
Tracking information is probably the most important thing the customer is interested in seeing after an order is placed! The customer wants to know "Where's my stuff?", and you don't want him bugging you about it.
This module lets your customer (or you, the admin) track shipped packages. It uses a hook to interface with installed shipping methods, so it can support tracking packages sent by any carrier, provided the hook is implemented. This module comes with hooks pre-written for FedEx, UPS and USPS.
It works by modifying the user order history page (e.g. user/4/orders) to display a clickable tracking number (or numbers) associated with each order. The user can click on the number and get real-time tracking details for his merchandise.
I decided to display the tracking number on the order history page so the customer wouldn't have to drill down and look for the tracking number - it should be right up top, since it's the thing they care about most. (This active tracking link should also be available on any page where the tracking number appears, but to do that easily requires modifications to the core Ubercart modules.)
To Use:
Install the uc_tracking module. Enable it at admin/build/modules.