Simon,
The data is skewed by default as it doesn't show who commits more crime, just who is a) arrested, or b) convicted for it. You can't use those stats to say "commits more crime"; it's bad statistical reading (not by you Simon; I'm referring to the sources who report it as such, of which you're probably repeating it from, as I've read that before as well).
The default comes in because black people are both incarcirated and arrested more, for the same crimes, as other people. Since they get higher arrests and convictions, you can't use that as the basis to say they commit more crime.
Media representation is skewed often based on the roles given. When I get calls for film, for instance, they only want a set number of black people, etc. or don't want Asians or Hispanics for certain roles, etc. Throughout film/television history, minorities were delegated to spot roles, while the majority gets broad representation (Women also have this issue as compared to men in other aspects).
Clear Channel, producers, etc. directly control music tastes of the masses with popular music. They directly choose what they want to push. Tupac, etc. got a following talking about real life struggles and dreams of the black children of the parents who grew up in more oppressed times, and were now living in ghettos with little chance to escape. Along with things like police harassment, etc. Producers saw this was successful in the underground, pushed this as the majority, and then it gradually morphed into what it is today, taking the "dreams" (money, women, items) and making it the entire message, while emphasizing the shirtless, strong, stereotypical "thug" look. Etc. etc. etc.
There are psychological aspects of oppression that are often ignored. Just as if someone is robbed by a black person dressed in some way, they may be more fearful of that look by default, so will a black kid be distrustful of cops if he's harassed and assaulted by them for no reason, or sees others who are. If someone believes a police officer will shoot them, even when unarmed, a flight or fight instinct will automatically kick in, which is a problem.
While it's fiction, I recommend The Wire - especially season 4, that basically follows 4 kids raised in the inner city, whose lives have wildly different outcomes, just by chance, basically (who they are exposed to, and when - or when things work against them in life and exactly the worst times). David Simon (the creator) was a reporter in Baltimore and based much of it on actual events.
I agree that poverty, education, and other things are all huge factors - but the whole thing is a combination of interlocking issues.