General WWII sources:

National World War II Museum - History

World War II History Reference Library from World War II History Info

World War II Multimedia Database

The Second World War Encyclopedia

World War II - MSN Encarta

The History Place

Other WWII pathfinders:

World War II 8th Grade Pathfinder

World War II 10th grade Pathfinder

Holocaust:

An Overview of the Holocaust [pdf] by Nancy E. Rupprecht Middle Tennessee State University

The Holocaust: A Learning Site for Students

United States Holocaust Memorial Museum

Simon Wiesenthal Center

Holocaust History Project

Children of the Holocaust

Anne Frank Center USA

Anne Frank House

CANDLES Holocaust Museum

A Cybrary of the Holocaust, Remember.org

History Place Holocaust Timeline

Teaching the Holocaust

Post War:

Nuremburg Trial