i have a 2002 wrx sedan with a hks DP, greddy evo2 tbe, no tune.
i was driving today and at about 75 80 mph i started to get an viberation in my car.
it got worse as i went faster, it got so bad i could see my hood wobbleing and couldent get to 100 mph before it felt like my car was going to shake it's self apart.
my lugs are good, but i know my front CV boots are both broken.
I think your profile said you're in Texas, so you wouldn't have the snow in your wheel problems that we have up here in New England.
It could be a band seperation in one of your tires, I had that in one of my cars, and as I drove faster, the more vibration I got. Do you feel it more in your hands/steering wheel (front tire problem) or more in the seat of your pants/seat (rear tire problem)?
My guess would be the rear, but try rotating your tires and see if the vibrating, and where you feel it changes. If there are no changes, chances are it's something else, if there are changes, its tire related.
I have a very similar problem on my stock 06 WRX. I had the front tires replaced and it improved but didn't go away. I think I feel wobble around 30 mph and 65 mph which is just weird. There is no wobble when I break so it can't be the rotors, right? Any luck with your car?