Wheel bears often make a fair bit of noise when they are on their way out. Usually you will notice a humming type sound when you are driving the vehicle and this may get louder at certain speeds. Another way to check a wheel bearing is to jack the wheel up and try and move it from side to side and up and down. If you can feel a lot of play in the wheel and it moves then the wheel bearing probably needs replacing.
If you take your car in to a garage they will easily be able to check if a bearing needs to be changed. The job usually takes around a couple of hours and can cost anything from £100 upwards of £300 depending what vehicle you have and where you take it to get the repairs done. Although it may seem like a relatively easy job to do, it isn’t if you do not have all the right equipment so it is better to have it done at a garage. You may be able to find a garage that will allow you to purchase the part yourself and them fit it for you, but be aware that if the part fails then you will need to fork out for the labour costs to get it replaced again as it will not be covered by the warranty.