n8pbm:
This will allow you to enter the tracking number in the admin and it will send an email with the tracking number to your customer:
http://www.zen-cart.com/index.php?main_page=product_contrib_info&cPath=40_47&products_id=167
Very nice addon.
I use the UPS part of it but didn't want to add the number each time I went to look one up, so I added this link to the UPS section of the module. Admin > Configuration > Ty Package Tracker > Carrier 2 Tracking Link
http://wwwapps.ups.com/WebTracking/processInputRequest?HTMLVersion=5.0&sort_by=status&term_warn=yes&tracknums_displayed=5&TypeOfInquiryNumber=T&loc=en_US&InquiryNumber2=&InquiryNumber3=&InquiryNumber4=&InquiryNumber5=&AgreeToTermsAndConditions=yes&track.x=15&track.y=12&InquiryNumber1=
This will take you right to the "Track Shipments" page and it will display all the information.