Tonight (US time), you can watch a live stream of the Winter Games New Zealand Mixed Doubles Curling Finals by clicking here. It will take place at 11:30 PM ET/8:30 PM PT on Wednesday night (which equates to 3:30 PM NZT on Thursday).
Japan will play Canada 1 in one semi-final and the USA plays Finland in the other.
Unfortunately, it appears the semi-finals are not scheduled to be live streamed.
**Update 1** The World Curling Federation will live stream the semi-finals and Gold Medal games here. The semi-finals begin at 7:00 PM ET/4:00 PM PT (11:00 AM NZT Thursday).