I'm traveling to Paris with my five small children over the holidays and I need to set up some extra hands to make this adventure functional. Is there a service like care.com or some other place to hire nannies and babysitters?
Have you considered bringing help with you? A grandma or friend?
If you're staying in a hotel, the front desk staff should have some ideas.
Hotels usually have some reliable connections, people who have been checked out thoroughly, have experience, etc.
I would avoid using anyone who advertises on the internet or on expat forums, because you have no idea who they are.
Here's a nanny service to investigate, though I have never used them:
http://www.nanniesinc.com/