Typical destinations of dead links are HTTP 404 ("Not Found") or 403 ("Forbidden") errors, or a generic search engine-type page proclaiming, "This domain is up for sale!"
If you see a dead external link on this wiki, correct it or remove it. If you see a dead internal link, then, in the immortal words of the instructions that appear when you click on it, "If you want to start this new page, just click the edit button above."
If you find that you can't create this page because it has been locked, that's because it's either a member of the Permanent Red Link Club, or it was made and cut previously. Check the Permanent Red Link Club for it, and if it's not there, go to this forum thread and request an unlock.
This is one reason why Weblinks Are Not Examples.