If you're site is going to be a huge success, it has to look better. It has to look professional. The current layout is somewhat confusing and lacks professional design. I know you just started it, and I'm not trying to offend you, only give you my honest opinion.
What you could really benefit from is a system by which each babysitter has a profile, which includes the things you currently have listed, but also their schedules, and a quick and easy form to contact the babysitter. this could send you the email first, which you then forward to them. It could also include a review system.
I use a similar system for my site
www.landscapersbay.com but it runs on the regional level and thus you search by city, town, state, etc. etc. But it could easily be tuned down to serve a single city.