If it get louder as you turn one diredtion while driving and quieter in the other direction, it is a wheel bearing.
The wheel bearing / hub assembly is a one piece unit, and unfortunately is not too cheap.
I would suggest that you replace it with ACDelco OEM parts. Only because I have yet to see one of the new design hubs go bad, and have seen almost every aftermarket cheap-o hub fail within 2 years of replacement.
Hope this helps.