Please note, as with all sports, you can only watch NASCAR live.
NBC Sports Live Extra
This can be found under Videos > add ons
You can access quite a bit of live game coverage for NHL, Premier League, College Basketball, NBA, MLS, NASCAR, MLB and Golf.
Go to live sports > First FirstRowSports.eu (or FirstRowSports.ge) > Motorsport
Go to live sports > Zunox.hk