I have gotten all my clients and interviews off of daycare bear, kijiji and godaycare.com. I hold my interviews Tuesdays typically as my older kids are gone to swimming lessons 6-7pm. That way my last client is gone by 5:15 and I am able to clean up, feed my youngest son dinner, prep our dinner and be ready for a 6pm interview and it it happens to run longer my hubby and kids arrive home and its the parents cue to leave.
I have also done Saturday mornings around 11 but I prefer not to. I do not hold them EVER during working hours.