I finally got it to work on my calendar project this morning at about 10:30am (in Seattle). Got an e-receipt. Then I tried a book and it got all the way through and at the very end said that there had been an error and to try again, so I did and got the same error. Tried about 30 minutes later and it worked. Problem was, I got 3 receipts for the 3 attempts (and each of those orders was for 6 books).
I gave it a couple of hours and then called the number on my receipt (1-800-676-2775) and got someone right away who went in and refunded the two extra orders and confirmed that all the other pending charges from yesterday would drop off in three days (20 pending charges). As a bonus, since the 2 extra orders have already printed, they're sending them anyhow at no charge, so now I'll have 18 copies of my book for the price of 6! All-in, I spent about 10 minutes on the phone. The woman I spoke to was great, new exactly what the problem was and how to fix it and was nice and on top of it.
Say what you will about Apple, but even though the experience was frustrating, it was quickly and professionally resolved, I'm getting even more copies of my book that will be great gifts for extended family, and everything will be here in plenty of time for the holidays (they already shipped). I think that maybe if we hadn't all procrastinated and ordered at the same time, we wouldn't be in this boat. Everyone makes mistakes.