This sounds like the kind of thing a wedding planner or the venue comes up with. Unless you're tasked with buying enough of these for fifty tables (or whatever), rigging and powering them, I'd guess every wedding designer has a different take on them. And these days, will they be tungsten or LED? If this is like some super-rich dude's wedding, try to get a few dozen LTM Peppers - tiny little 200 watt tungsten fresnels. Give yourself a few months to track down that many though, and then go to filmtools.com to get all sorts of rigging gear!.
My guess is these days you'd use something like track light fixtures, which may be 120v, or 12v. or 120 to the fixture with an integrated transformer at the ceiling mount. Most of those still seem to be tungsten/halogen but LEDs are taking over everything.