FindABabysitter.com.au – Australia

This is a massive database and probably best for someone who is looking for a longer term childcare solution.

You basically pay 75 AUD for 3 months for unlimited access to a database of thousands of caretakers, each with their credentials, certifications and experience listed. You can either browse by specific criteria, or post your own request and have people respond.

Warning: you may be completely overwhelmed by the number of responses.