We booked with All Seasons Travel over 6 months ago (still another 6 months till we cruise) and we did receive written confirmation in the mail a few weeks after booking. Every month we make a payment towards the cruise and within a week or so we receive new paperwork, showing every payment we've made up to that point, and the balance remaining.
If you don't get anything in the mail in the next couple of days, you could give them a call. They have an 800# and they can tell you if it's been mailed out yet.
P.S. Have you gotten an email from them? Each month when I make a payment, I get an email showing the payment, PLUS the written statement in the mail.