Humming sound at high speed?

Any idea what would cause this? About 6 months ago I was traveling from Charleston, SC to Tucson, AZ and had to stop in Tenesee to get my front passenger side tire changed. Since then I have notice that anytime i'm going over 60, when the road starts to curve a little to the right the car starts humming. I't never makes this sound unless im going over 60 AND turn the wheel to the right to follow a curve in the road. I also noticed the the outside edge of the passenger side tire has a little more wear than the rest of the tires. I took it to the sears service center for a tire alignment and while there asked them if everything looks ok, they said that there was nothing wrong with it, everything was within specs.

When mine started making a humming on slight turns it was the warning sign that the front wheel bearing was going bad. It kept getting louder until it was replaced. Mine was the wheel bearing opposite of the direction of turning.