First, I dont agree with assaas0803 said we should use right leg to protect the ball while we are dribbling. plz watch this video, although it is just a video to teach you how to crossover, it teaches you the way of protecting the basketball also. http://youtube.com/watch?v=YHjvl8qCQqM
If you dont want to be stolen by others, you better keep a distance with your defender if and only if you have to dribbling facing him, what I mean is Face to Face, however u can use ur side to face ur defender therefore he cannot strip off your ball. This is what NBA players always do.