What about looking around in your neighborhood with people you know and who know you?
Your child's school is a great place to start.. ask other parents, teachers, etc for references.
When we had our daughter, we started out with a service in Dallas that was called AAA and we used that service while she was very young and had the same person every week for our date night. Yes, they had higher fees but we knew whe was well cared for.
After she was a little older, I found teens in the neighborhood and still paid VERY WELL to keep them interested in babysitting. We had 1 family who had 3 daughters and we used all 3 daughters... as 1 would move on to college, the next in line became our sitter..
Our daughter is now 18 and she babysits regularly in our neighborhood. Also, our HOA has a website where teens and adults can advertise sitting services, etc.
Try to find someone local that you know or know through someone else.
Good luck.