flights from US/Eastern Canada?

[wendyt_ca]

I am trying to find cheap flights from NYC to London one way for September 2. The cheapest that I can find is $400 each one way. This is the first time I am going so I am not sure if there are ways to get it cheaper. We are from New Brunswick Canada but from there or Halifax it is $1200 per person so for the price difference we can catch a quick flight to NYC for $150 round trip then fly to London. We are also going to be coming back on Sept 12 from Paris. Does anyone know of any cheaper options?