Although the official partner for Canadian residents isn't yet online, our US counterpart CoSport is taking advanced registration for lottery-based selection of event ticketing now until the 31st of May 2019 for "non-binding" requests.
Check out www.cosport.com/olympics/tickets.aspx or let us know you're interested and we can try to help guide the process or secure you a package in advance!
Live inventory should be be available some time in July.