BarelyThere, different Bibles treat those verses differently. They might have the scripture with a footnote explaining the issue or they may not. One Catholic Bible that I had actually had that scripture at the end of the book of John with an explanation as to why it was considered spurious.
If you go to biblegateway.com you'll find nearly 50 different translations some of which explain why this was considered spurious scripture. The New International Version says:
"[The earliest manuscripts and many other ancient witnesses do not have John 7:53—8:11. A few manuscripts include these verses, wholly or in part, after John 7:36, John 21:25, Luke 21:38 or Luke 24:53.]"
The fact that this scripture is found in many different locations is as telling as its not being found at all in other manuscripts. It indicates that this "add on" account took a while before it settled its position in the text of the New Testament. To make an analogy the evolution of this spurious text was like adding a foreign gene to DNA.