When booking comes from Expedia (which works on Sabre system) the ticket number is also not shown on CheckMyTrip (which is Amadeus), but it's always visable within the itinerary in Expedia. So try checking the Orbitz itinerary online.
You can also have a look on the credit card statement, if the airline charged you directly, there is sometimes a ticket number as a title of the transaction.
Life is short and the world is wide...
Programs: FB Gold, M&M Frequent Traveller, BA Bronze
It's scary, you always need to make sure you've got that ticket number, somehow. I once turned up at FRA for a CSA Czech Airlines flight, having paid and printed the reservation, and was told there was no seat for me because no tkt number had been issued.
Today, Air Europa called me, about a problem issuing the GVA-MAD-GVA reservation. They needed the security number on my credit card, and it had been impossible to do it on their website during the reservation. I wish I had thought to ask, before the tkt was finally issued, if it was possible to add a flight at the MAD end of trip, namely to VGO. It might not have been too dear in conjunction with an international ticket.
Also, I think that tickets with a reservation date far in the future get issued a lot later than one expects. So it is possible that your ticket is queued but simply not issued yet.