What post office are you talking to? If you're 
talking to the one that *accepted* the package, 
then maybe you can call and try talking to the 
one that was last known to have had it. (Meaning, 
the post office where it was last scanned.)

I've had this problem, not only with mail but 
other related things (like luggage on airlines) 
as well, and the "traceable" part of the equation 
is reliant on people actually *scanning* the bar 
codes used to trace the item. Often when things 
are rushed, no one takes time to scan the bar 
codes on the things. Or they only scan it when 
it's coming *in*, and not when it *leaves* again. 
(Creating the false appearance on the website of 
it staying in one place for days on end.)

I've found that traceable forms of mailing only 
go so far because the bar code scanning is 
generally too sloppy. I would call the post 
office that you know had it last. . . If they 
can't tell you where it is, then report it 
missing. (But keep in mind that the post office 
has their own idea how long it takes for 
something to be officially "missing" - that's why 
they won't answer you regarding a search for a 
money order until 60 days have passed, etc.) Make 
sure you find out how long they "need" to wait 
before admitting they lost something.

Good luck!! ^_^;;;

Many Sharp Smiles,
--Drac