The Classic Edition includes:

Wasteland 2: Director's Cut
Wasteland 2
A free copy of Wasteland 1 - The Original Classic.
Mark Morgan's Wasteland 2 original soundtrack in digital format.
An incredible digital concept art book showcasing many of the world's characters and environments.
The extras can be found in your Steam installation location for Wasteland 2. (e.g. C:\Program Files\Steam\SteamApps\common\Wasteland 2)