The Groundwork of Evangelion is a collection of 5 artbooks which contain a large number of production sketches and a few colored plates in the beginning of each one. The first covers episodes 1 through 8, the second covers episodes 9 through 19, and the third covers episodes 20 through 26. The last 2 books are called Groundwork of Evangelion the Movie #1 and #2, the first covering Death and Episode 25' and the second covering Episode 26'.
This article bears the unpleasant designation of "Stub." This is a Bad Thing. Provide a great service to NGE fan-geeks everywhere by making it awesomer!