I had a similar problem on my Renault Megane coupe about 6months ago. I posted a similar message to yours and got the following advice:
Jack the car up under the wheel(s) concerned, take the hand brake off and spin them fairly quickly - if the humming noise happens then, then yes its the bearings!
Took the car to a local garage, £35 per wheel for parts (I had two done) and 2 hrs labour. If your looking to buy them yourselfm try
- I looked (but didn't buy from their as didn't have the kit to do it myself) and from memory the parts were fairly cheap on their.