is that covering stuff that is on all these planes paintable? If not, how can you get all these neat designs that I see?

c'mon fellas, I really want to know this!!!

it's paintable, goto towerhobbies.com and look for ultracoat paint

Most color schemes you see are done with the covering material, and that is the most durable way. You can paint plastic covering, but IMO it won't look as good, for as long.

As aernaut said most of the designs are made using film. If you look in the tips and techniques forum there are some really good threads that talk through techniques used to do some really great looking graphic effects.

Good luck ... Bo