For both my kids (who are 7 yrs apart) I went with Family DayCare (i think is$650/month) because:
* criminal background checks are required
* slightly more affordable than Wee Watch
* didn't want a day care centre, but a home service
* the agency does unexpected drop ins to see how things are going
The agency gave me a list of providers in the area I requested and I got to interview them. Trust me your gut instinct will steer you in the right direction. I knew right away which ones I did not want to use. I found two fantastic sitters that my kids just adored; my son stayed with his until we moved and my daughter is still with hers. My sitter left FD but I just went private with her. Good luck, it's very hard to find good sitters you feel comfortable with, but they're out there! Also, have you checked here? I have used them to find my occasional evening sitter: My girlfriend & I split the fee.
www.canadiansitter.ca