We looked into getting a nanny share with friends about six months ago. It was about $9-12 / hour for one child, depending on the nanny's experience. It's usually about $14-16 / hr for two children, which is why we were looking into a nanny share. Craigslist and urbanmamas is a good place to find nannies or connect with other parents looking for a nanny share.
Warning
No formatter is installed for the format bbhtml
$12-14 is what you'll most likely pay per hour. Also remember that legally you need to pay nanny taxes. It adds up, but for us it was the best decision for the first 2.5 years. We didn't have to worry about getting the girls ready to leave the house in the morning if they slept late, and the nanny also took care of cleaning the kitchen and the girls clothes. Ah, I'll miss that.
Re: Cost for part-time nanny?