Playing the Air Fare Game

I'd like to get some advice from the readers of this board on how they play the airfare game.

Next May I'm planning on flying from either BOS or JFK/EWR to London (LHR) and then taking the train to Scotland. Today for nonstop flights (my preference) prices range from $918 (Kuwait Air) to around $1200 for AA, DL, BA,& Virgin. I know that prices change from minute to minute, but are there better times to lock in a decent price? How long would most of you wait to get the fare you want without jeopardizing getting to your destination without bankrupting yourself. If Kuwait's flight is the best that I can find online, will other airlines match their fare?

Any tips - or sites for tips - would be greatly appreciated.

We love British Air, but they have become very expensive and non- cooperative on using miles to upgrade. So, we are flying Icelandic Air for our trip to Paris for Christmas. To breakup the trip, we are spending a night in Reykjavik.
Price was right and the stop over should be interesting.

first clear your cookies no kidding. . .i am going to milan in may. airlines have algorithms(sp?) 24/7 that watch which way to see how you are searching for ticket prices. that being said if you see anything under $1,000 RT nowadays take it. tried to do the one way to milan and one way back from somewhere else and way expensive. too bad used to be to fly to London would be a cheap way to go to get somewhere else in the Uk but not anymore.

to add to this from boston or JFK to London for $918 sounds kinda expensive. I got two RT tckts from tampa to milan for $2000 in May. United. I know totally diff regions but . . .

Agree with clearing cookies but do you think signing up for fare alerts with kayak, yapta, and hipmunk still does the same thing? I am trying to find reasonable flights from Midwest to Rome for next June. Most everything is $1700+ or has a terrible schedule. I am hoping it drops some soon. Any thoughts as to a time of year it will drop for next year? I know sometimes there are sales on holiday weekends. I have not bought tickets for Europe before so new territory.