Westjet is having a seat sale from Toronto to L.A. for $278CDN, taxes in. That deal is $70 less than Air Canada's current prices at the same time period. The deal are for select direct flights from November to February.
Book now by going to Google Flights, and then opening up their availability calendar by clicking on my pre-chosen departure date. You'll then see the prices for departures for every day of the month. After choosing your departure date, you'll see the prices for returning dates.