Patti- Though it was not a Lexus, I had a 2006 Trailblazer SS before this car that I had to replace both front wheel bearings (Chevy's are known for that problem). Your symtoms do seem like they maybe wheel bearing related based upon your desription. I would say try the right one first. Since the sound changes only when you make a turn one way but not the other, often times that is an indication that the opposite wheel bearing has gone bad.
Denny- Thank you for the welcome and for offering your thoughts. I have checked everything wheel related and we where looking at the drive shafts. The rear shaft is in alignment. I just noticed that my rear passanger rotor is getting hotter than the others. It looks like there maybe a stuck caliper causing an issue though it is not grabbing very hard. I think the friction maybe causing the vibration. I didn't think to look there since the brakes were just done last year and that happens to be a calliper that was replaced because it was the floating pin was rusted shut.
I have it going into the shop on Monday. I will let you know how it turns out.
Thanks again,
Scott