For power polishing I found an excellent resource from Caswell: How To Buff And Polish. All of the supplies were at my local Princess Auto:

6" spiral-sewn buffing wheel (x 1)
6" loose cotton buffing wheel (x 3)
4 oz. Polishing compound, Brown Tripoli (x 1)
4 oz. Polishing compound, White Diamond (x 1)
4 oz. Polishing compound, Blue (x 1)
4 oz. Polishing compound, Jeweler's Rouge (x 1)

I mounted the spiral-sewn wheel and one of the loose cotton wheels on my bench grinder; the Brown Tripoli compound went on the former and the White Diamond on the latter.



Afterwards:



The next step were the blue and the Jeweler's Rouge compounds, both onto new loose cotton wheels.



Now, Caswell says the rouge is the finer of the two so I started with the blue and moved to the rouge. I took another look at the packages, however, and the compound manufacturer shows the blue to be the finest. So I finished with the blue. The final result:



.....

Reflections (pun intended) on the polishing process:

The Flitz method:
Good results and, once you realize that all of the oxidation can never come off, fairly quick. At $12.99, Definitely the cheapest.

The Tru-Turn method:
Poor instructions and results to match. About $15 in sandpaper - and you still need the Flitz.

The power polishing method:
Quick and easy. The most expensive, though, at about $45. And that's if you already have a grinder.

In conclusion, I'd recommend the Flitz, at least to start with. Lots of folks recommend Mothers Mag & Aluminum Polish so that's certainly an alternative. I'm not sorry I tried all three methods - I sure learned a lot and hopefully some of it will be helpful to others.