eBay Tracking Number System

[toasterink]

I purchased two items, from different sellers, and eBay Tracking indicates that both items were delivered on same day.  Shipping name and adresss were correct.  Unfortunately, they were not delivered to my mailbox.  USPS says they have no way to track what happened to the two items using eBay Tracking numbers.  What recourse do I have?  Is there any way to correlate eBay Tracking number with USPS Tracking?

[wastingtime101]

Were they trading cards with ESUS numbers @toasterink?

I always use this page to track ESUS numbers because it'll give you more detailed carrier info, but I'm not sure if it works with eBay Standard Envelope service.

[toasterink]

They were collectible post cards, presumably sent First Class.  I checked the EasyShip page you referenced and will share the info I found there with local USPS.  Seems like if USPS enters final tracking info, there should be some way to trace with whatever system generated original number.