K.D.
We had a biter. I flicked his cheek enough it smarted. If nothing else, he learned that that action caused him hurt. Eventually I had to just end the feeding and put him down. It took a few weeks, but we were able to finish out the rest of the year. You have to do it every time, no matter how hungry he may think he is. The hungrier, the faster he'll learn.
If you decide to wean, drop a feeding every few days like was mentioned before. Also, if he has a hard time with dropping one, giving him yogurt instead of nursing will help. Check with your doctor, but it should be fine. Mine was over a year when we weaned, so we also used milk with a touch of chocolate. The idea is something sweet so they don't miss the milk as much. I dropped them starting with lunch, dinner, breakfast, then night. My second weaned as soon as I dropped the second feeding. Ouch!! I found that cabbage leaves inside my bra did more than anything else to relieve the pain. It seemed to relieve the engorement, as well. Sounds wierd, but it works instantly. Just replace them with a cold one once the effect wears off. They do look funny, so don't forget to remove them before leaving the house. :) GL!