The most miracles that I have seen have been through tracting. The first day, we didn't have much success with people (as far as I could tell). The second day we went tracting was AMAZING, though.
We knocked on one door and this family answered who were Christian (don't remember the religion) and they talked about a program where they teach Christianity to Native Americans in the West (including Navajo). Long story short, we gave them a Book of Mormon, prayed with them and left. They were really nice, and I hope that the father (he wasn't home, but we know that he is a pastor in their church) is the same way about us.
The next house that answered after this family was a lady from the Faith Assembly of God Church (famous around here) and she wanted nothing to do with us and was about to shut the door when my companion asked her if we could say prayer before she left. She agreed and we prayed and she closed the screen door as we started walking away. When we were halfway down the sidewalk, she opened the screen door and started the conversation again. She is planning on attending our church sometime. A completely different countenance. It was amazing.