There are several good daycare options near Butler. I know people who have had their children at the JCC on Elmgrove, YMCA on Hope, Lincoln School on Blackstone (smaller, and hard to get into because Lincoln School teachers get priority), and Cozy Corner off of N. Main.
I know several Butler docs who had their children at Cozy and were very positive. I've heard not-so-great things about the daycare on the Butler campus (East Side Learning Center?) from multiple sources.
Costs really vary. We paid ~$1700/month at the JCC when my child was an infant. We moved, so i can't speak to the costs for older ages - but it will obviously be cheaper for a 2 year-old. I believe that the JCC is on the higher end, though. The Y and Cozy Corner are supposed to be more reasonable.