What to pay a babysitter really varies from state to state and even between metro areas within a state. Besides just asking your neighbors what they pay, another way to figure out is to call some in-home daycares and find out what their hourly rate is. You would usually pay a teenage babysitter a dollar or two less that you would pay the daycare provider. I personally pay $7 an hour for three kids.
I think it is according to where you live. I know a personal sitter where I am in Canada is 10 per child per hour. But you can also get better deals from teenagers or moms that work in there home. good luck!