Hi delizar,
Im in the same position as you i started off with a LT-40 and want to move as fast as i can to a p-51D mustang. If your looking for a .40 size warbird you might be able to get it as a third plane. First you need a trainer almost all trainers on the markets are good exept if youre building a kit and dont know much about building planes i also suggest going with the kadet for me i had no experience and i found it pretty easy to build. Everything comes precut and very little sanding is nessesary. It will be an easy plane to build, fly, and learn the basics with. Then the next step will be to get a taildragger low wing sport plane something where you can transfer from a trainer to a low wing to get ready for the warbird. There are many good planes out there but you wont half to think of that for a while. Then you can make your way to your favorite warbird.

Papa