What country are you from?  Think about this: The US has the Library of Congress to keep archives of our history.  Other countries would have similar organizations.  What keywords would you use to find the official archives site of your country?  What is the domain for your country?  (.uk, .jp, .de, .fr)  Try an Advanced Google Search and narrow it by the domain of your country.

http://www.history.com/topics/world-war-ii battle accounts, etc.

http://www.bbc.co.uk/history/worldwars/wwtwo/  WWII history from the BBC – British Broadcasting Corp. 

http://memory.loc.gov/cgi-bin/query/f?gmd:0:./temp/~ammem_NV35: maps

Library of Congress more battle maps

http://www.loc.gov/topics/content.php?subcat=11  Other WWII info from the LOC

http://www.nationalww2museum.org/  WWII museum

http://avalon.law.yale.edu/subject_menus/wwii.asp  WWII primary source documents 

http://www.pbs.org/thewar/at_home.htm  A great resource with many features from PBS.