Maybe you need to learn a bit more about those sites then. They may have admitted to being biased personally but at least they publish all of the news wires (at least I know Breitbart.com does anyway)
It would be impossible to locate a purely unbiased news source. It doesn't exist. Even the wire services themselves are biased in their reporting unfortunately. That's why you need to analyze the actual substance of the news piece yourself and do the best you can to identify the source of the bias itself.
EDIT: You're referencing Media Matters which is about as far left as you can get so ironically, it's severely biased and I wouldn't trust a damn thing they write.
Breitbart simply licenses Reuters and AP stories, and Drudge simply links to other stories. These liberal bitches are really getting tedious.