I know from experience that you can't get those stains out by hand. I have a set of those wheels.
There are two ways to polish the wheels that makes it very easy. The first is the Mothers Powerball, which works well for the price. I use that along with the mag and aluminum polish.
The second and better method is with the flitz power wheel. It's a more robust polishing ball and really can bring out the shine. It's also more expensive, but works faster still.
With either of these methods all your wheels will look much, much better after about 1/2 hour.