For the look above, I used U-Concrete-Me from shades (Barielle). It's a nice medium dark grey that dries a little darker than the color in the bottle. For the black and white ribbon accent, I painted layers of overlapping black and white. This would have been a whole lot easier with striper polishes but I couldn't find mine at the time. The black is Misbehaving Mistress from shades and the white is China Glaze White on White. Here's a step by step wheel if you're interested in trying it out:
Hope that helps! Feel free to let me know if you have any questions / comments.