In the past a common practice to find a bad bearing was just shaking the wheel (based on assumption that bad bearing will have a lot of clearance). While it is true for double roller bearings, a typical sign of ball bearing failure is a dent or nick on the race, so there will be no play but the noise.(Common trick to turn from side to side will not pinpoint this problem either)
http://farm7.staticflickr.com/6224/6233150546_bea61b3497.jpg
And this is how the defective race looks outside:
http://farm7.staticflickr.com/6053/6235873319_81a8521ba2.jpg