Wow. What a totally unmanageable topic. You need to limit the report to something manageable:
-racism in the 2008 election
-racist groups in the US today
-anti-racist initiatives
-American perception of racism
-German perception of racism in the US
-etc.
All of those are still very broad topics.
maxxpf's suggestion is a good
starting point. In the US, though, Wikipedia is not accepted as a source for a research report - I don't know about Germany. Some of the external links look promising, though. For example, the link in footnote 141 takes you to the Southern Poverty Law Center, a recognized anti-discrimination organization.
You might also try some of the links here:
http://www.google.com/search?q=%22racism+in+t...The link to PBS takes you to an article from the Public Broadcasting System, a recognized educational source. The American Civil Liberties Union (ACLU) is also a recognized champion of civil liberties and rights. time.com is from Time Magazine, a respected news magazine in the US. I would be wary of sites with an obvious agenda (e.g. socialistworker.org).