Any way to do it before apple confirms its shipping ?
If it's going by UPS all you need is your original order number (starts with a W), not a tracking number, then follow the instructions given above and elsewhere. DON'T put any other info into the UPS tracker like your postcode, JUST the W number in TRACK BY REFERENCE.
I know people are saying to use one of the other numbers provided when your item status changes to SHIPPED, but my W number works for me.