Hi Sassygirl,
I agree with Frank, in that the available options to get to Ensanada are not very reliable. While I haven't sailed Celebrity out of Ensanada we did sail on RCI's Vision of the Seas. We purchased transfers from RCI, iI believe they were about $65 apiece, and took the AMTRAK train from Orange County to San Diego, and a taxi to the airport. There was a little confusion at the airport but we just had a short wait until we were on a bus for the 2 1/2 hour ride to Ensanada. There are a number of stops along the way and We had no problems because the bus was cleared and fees payed by the cruise line. Celebrity in a part of RCI so you should be able to get the same opportunity for purchasing ground transport. Your Celebrity brochure has a statement saying the transfers can be purchased if you have made your own flight arrangements.
The cost may seem high for this transport but you get a box lunch and a bottle of water, all tolls and fees paid, cruise check in at a hotel in Ensanada and transport to the cruise terminal. The busses were air conditioned and a party atmoshere prevailed on the trip. If anyone refuses to sell you transfers I would certainly go up the line of authority until I found out why not.
Peter