I am looking for a short story about time travel. In the story some one trips over a butterfly and they can't find their way back. Does any one know if this is a Bradbury story or what the name of the story is if it is his story. Thanks

It sounds like, "A Sound of Thunder" by Ray Bradbury, and published in: "R Is For Rocket" and in "The Stories of Ray Bradbury".

Great story.

This amazing story can also be found in THE GOLDEN APPLES OF THE SUN and TWICE 22.