Bitcoin Gold listed on some exchanges following the October 23 soft fork, like Bitfinex and Yobit.net for example, while many other exchanges simply ignored the coin, and have chosen not to carry it.
Some of the exchanges that are trading Bitcoin gold can be found at the Coin Market Cap site where the markets are illustrated:
The price has dropped considerably since its inception on the October 23 split date, moving from .08 btc to around the .02 btc price point. It is unclear whether this coin will get any momentum and be adopted on other exchanges, or how it will play out across the exchanges, especially since there is no clear winner yet.
The BTG website has some useful metrics for the next Bitcoin split, illustrating how the various coins are similar and different:
Regardless, this will be an interesting coin to follow.