M.C.
Check farecaster.com to see their prediction for whether prices will go up or down for your itinerary. Kayak.com will give you a graph of the fare for the past 30 days, so you can see if it's gone up or down recently. Sign up for alerts from kayak when the price hits your desired level (be reasonable, here--a transatlantic flight will never be $20!). Sign up for the travelzoo and kayak weekly deal emails, to watch for international sales. They do come up periodically, and can be quite good. I don't think that you need to be in a rush to buy a ticket this week, but I would do your research so you know a good fare when you see one, then jump on it when it comes up. Airline fares are always a bit of a gamble--you can get great deals last minute, but if you know you need to go, you don't want to count on that. GL!