I ordered something online, and it's suppose to arrive soon...?

I ordered a something online fairly small, a book. Well it was suppose to arrive 2-3 days. Today is the third day so here I am anxiously awaiting. Well, I live in some apartments and i'm just wondering. How will they drop it off? Will it come with the mail? Since its a book i'm guessing it'll fit in the slot. If they bring it to the door will they just knock and leave it there? I got several e-mails but none of them said anything about a signature requested or whether UPS or FedEx was bringing it. So... these are my questions.