Front End Vibration at speed
 

I have noticed a vibration coming from what feels like my front right wheel. It begins to make a low frequency noise (almost like a rubbing) at 30 mph and gets louder and faster up to about 50 mph...then it goes away. I say that it gets louder but at its worst it isnt much louder than the road noise. Is this most likely the wheel bearing? If so how much will Porsche charge me to get it fixed? Or is this a job I could handle myself? Thanks much. Thought I would ask the pros before I took it in.