What will I get from Princess when I book my cruise with my travel agent? I believe that all boarding documentation is electronic, so that won't come in the mail. Should I be expecting a package of some sort (will it come to me at the time of deposit, or after my final payment)?
Yes, it'll come about 75 days prior to your sailing. In it, you'll find your luggage tags, shore excursion info., cruise information booklet and other miscellaneous information sheets. It's kinda fun to get even though it's not the actual documents. You won't need to send anything back to Princess like in the past.
You can print out your "documents" online after you complete the immigration information and about 6-8 weeks prior to your cruise. It's just a piece of paper for boarding from what I understand. You have to do this more than 5 days before your cruise.