Al Jazzera English also can provide an interesting alternative perspective.
Originally set up with a lot of former BBC employees, and so had/has a fair amount of credibility, though its funding by the Qatar government does raise questions (and reason for some caution).
Most mainstream media are more centerist (CNN) to right-wing than left... despite the claims and protestations from those on the right.
Look at the ownership of the major media organisations and what their agenda is.
If you want to taste some left-wing media, take a look at Democracy Now, or possibly Huffington Post.
