Snopes.com calls itself "The definitive Internet reference source for urban legends, folklore, myths, rumors, and misinformation." Here's a link to some of the more macabre stories they've looked into. Some are actually true!

http://www.snopes.com/horrors/gruesome/gruesome.asp

Once you've satisfied your curiosity about the macabre, do some poking around in the rest of the snopes.com topics. I bet you'll find more than one that you've heard and maybe even believed. Remember the one a few years ago about the cat that came back from the dead? No, it wasn't Pet Sematary. It was an "actual, true story" that I heard from "someone who knew the people it happened to."