How long does it take to receive a permit in the post/mail?

Apparently my employer received a copy of my green card permit a week ago from today. I'm located in NYC and still do not have it and my flight is next week. Is this usual to not have it after a week? What are the usual timelines for this sort of thing? I just want this agonizing wait to be over with and on my way already!

It would be nice if they gave you a tracking number or something at least, geez.

If I call them tomorrow will they be much help?

If I don't receive it before I leave, can they resend me another one to my employer when I'm in the country?

Problem is they failed to put my apartment number on the permit! This is why I do not have it!