I utilized several different websites but the main two were http://www.guinnessworldrecords.com/ and Google.
I had students analyze several different stats from the World Record Book and then we used Google maps and Google Earth to see where the world record holders were located. I also had students make a Google Presentation about World Record stats that they found. In general students used Google Docs to keep track of the World Record information that they researched.
We also used http://www.blurb.com/ to make our own Amazing Book of Class Records.