If you want to build a plane from a pile of wood, I definitely recommend building a commercially available kit over trying to cut each part from large sheets or sticks.

A first build (using a kit) is a huge learning experience. It usually takes longer than you'd expect and there are times when it can be frustrating. The frustrating times usually start about the time you recognize a mistake and have to figure out how to recover from it.

Cutting each part would add too many recovery opportunities for me and I'd never finish.


I mention the Great Planes kit line-up because they have the manuals for many of their kits available for free download:
http://www.greatplanes.com/parts/index.html#kits
The PT-20 & PT-40 share the same manual. These are fairly typical "Primary Trainer" kits. The biggest majority of trainer kits are very similar and the 'which one is best' question is almost impossible to answer. In reality, if you want to build a trainer from a kit, any of the ones in RCKen's list will be perfectly fine for learning to build and fly.