This case that was featured was about an old man traveling through the Northern states (Montana, Minnesota, or Wisconsin I believe) and was killed at an isolated rest stop and was found at a trash dump. There was a mysterious man seen at the rest stop. Thanks in advance for your help.

Dexter Stefonek. Do a search on the boards for more info and threads pertaining to the story.

I live in Montana, and my boyfriend is from the town where Dexter's body was found. To the best of our knowledge, there have been no updates to this story.

Yes, Dexter Stefonek. You might want to check out
http://www.leighlarson.com/vivian_e_abbey.htm
Maybe Mr. Larson might have some information for you?
I still think this is a very strange case. A truck with Arizona tags,
his car is set on fire there even though the body was dumped down the
road, and writing on the bathroom stall with the date and destinations
of Stefonek's trip with the words "hot jock".

btw, a friend of mine was watching that "all your base belong to us"
video right after I saw this episode and I freaked because I recognized
one of the signs. It was a sign for the Bad Route rest stop where
Stefonek was killed. Just go to http://www.theslowlane.com/93tripc/bad.html#video
to read about it.