Grade 9 students in Clay Burell's world history class at Korea International School created this multimedia wiki textbook covering world history from World War I to World War II and the beginnings of the Cold War. It was created in June 2007.
I am open to allowing expansion, editing, fact-checking, mash-ups, and any other possibilities suggested by any interested parties.
This "learning pursuit" site though not a WebQuest does give students tasks and resources. It was created for 12th grade IB History students but can be adapted for younger non-IB students. It covers some of the main topics for the European events of WWII.