Unfortunately I don't know precisely to whom the credit goes!
The majority of the icebreaker and team building activities I use have come from Jim Cain's various books (Teamwork and Teamplay, Teambuilding Puzzles) or publications by Edie West (201 Icebreakers).
I have however put my own spin on many of the activities and I certainly encourage you to do the same. Keep in mind these events are supposed to be fun. So use these ideas as a launching board for your own imagination and initiative.
If you are looking for a good book of ice breakers, here's one I recommend from Amazon.com. You can check it out by clicking on the link below: