Hi Lisa
The only ways is to find those long cars in the trains in the Train manager or in the train itself on the farms.
Remember that the train has to be back home and unloaded before you can remove any car from it.
Also, you can leave the long cattle car in your train and then sell the animals at market.
You go to Trade market and you click in Items tab and set it to Animals.
About the amount of trains:
You can have 3 of each of the different speed Locomotives, making 15 trains in total.
ONLY ONE of the exact same speed Locomotive can be on the same farm and be dispatched to bring you products.
If you buy more than one of the same speed locomotive they must be placed on different farms to be able to dispatch them.
You can have 5 trains on a single farm at the same time*as long as*each of those trains has a different speed Locomotive.
If you still want to make a suggestion, then please post it in our Suggestion section.