Beth, AmbrrNanaDog was a real biter as a puppy.  She's a shelter alumni, so who knows her history.  She is THE BEST dog on the planet (next to Gabriel, of course) and I stopped her biting by circling her snout with my fingers and one finger across snout in a tap, with NO BITING.  When she would go crazy aggressive, I would roll her onto her back (she was probably under 8 weeks) and I have to tell you she went fromthe worst wild child to the best behaved hand command trained dog.  As Andrea will weigh in, you can reinforce her good (non-biting) behaviour with the click and she will learn when she stops biting that is a GOOD thing and hopefully will get into the 'please the human' frame of mind.  Most dogs crave our love and approval, and that is the greatest motivator, love and happiness. 

As my NanaDog will tell you, when Mama aint happy aint nobody happy :)