Onlythebreast.com
You can buy, sell or donate breast milk. I dont know much about it, though!
Milk banks are for donation. It goes to premies who's mothers cant or don't produce enough milk ect. I see ppl selling for money on Craigslist. I personally would never buy milk from Craigslist though. You never know if mom drinks/smokes ect.
I didn't know there was even such thing! Id like to know too!