I was going to say exactly what Erica did, when she bites, pull her into your breast so she has to choose between breathing and biting, she will let go right away, then you say 'NO BITING' very firmly, and be done nursing for that session.
She is NOT weaning, please dont let anyone tell you that.... too many people wean early when thier baby bites, or goes on a nursing strike, its not weaning, its normal development so please don't let anyone convince you to stop.... there is no reason to.
Both my boys bit, both right around 9mos old, and it was related to teething. My oldest only took once of pulling into my breast and he stopped. My youngest was (and is!) more stubborn and I had to do it 3 times with him, and he stopped. :)
If you are really nervous about hte biting, keep your pinkie finger poised at the corner of her mouth. If you feel her starting to clamp down, stick your finger in her mouth and it will stop her from biting... as your finger will be wedged between her gums. But the pulling her to your breast will send a message, and she will stop.