Carry extra spokes for the rear wheel, and carry a freewheel remover if you have a freewheel and not a cassette.
As for maps, you can see the details of maps on ACA's web page. Print them out. You can use them to route your course. If you look at how the lines run on their maps and the towns they go to, you can pretty well look on standard road maps and see which roads they are using. Actually, some of their route takes you through areas that are much hillier, but no more scenic than other roads, or at least that was what I was reading in journals written by people who had used ACA's maps.
Interstates 10 and 8 are good for cycling where no other roads are available. Going west to east will have you eating a lot of headwinds. Many say west to east is the way to go, but if you read Donna Ikenberry's book on the Transam, you will see she chose east to west, and she tells why. I did more research on the internet, and have done the southern tier a number of times. East to west is a good way to go. Of course, in your situation, west to east is the only way to go, but I thought I would mention it.
Trailers are fine. I have never used one, but I have read journals by those who have. One thing about trailers. They add more wheels, and tires that can wear out. You need to carry extra tires for those odd sized wheels. There is a connection to the bike, and these connections have been known to break. The trailer adds its own weight to the load you already have. In my way of looking at things, adding a trailer is just adding more that can go wrong, along with extra weight.
This message was edited by Westinghouse on 10-16-08 @ 12:10 PM