Welcone to the hobby!,
You will be suprised how easy trainers are to cover. Monokote is what I started with and it is a good product. But so are most of the other covering options.
These guys are really good help when you have questions. I think the take your time advice is VERY good. Craftsmanship counts in this hobby. Now having said that its ok if your first plane has a few wrinkles REALLY! Trainers get beatup so don't sweat it to much. Your choice of plane is a fine one, The PT will be easy to fix and you will be able to make repairs better for building it yourself.