There is a huge variety in lights available for cable systems. They come in different widths, for cable separations from 2″ to 36″.
You can also adapt lights for other systems to work on cable using a Freejack connector from Tech Lighting or a uni-plug adapter from Bruck Lighting. Because the cable is the same size, the lights are compatible. However, if you want a very consistent look, choosing lights all from the same company will make sure they all have the identical finish.
The easiest way to start is a kit. This kit from Tiella, a division of Tech Lighting is a good place to start. Tiella 800CBL5P, 800CBL5PN Accent 5-Light Cable Kit on Amazon