The process describing how defunct web sites can be removed from Google search index is described here
using the "Google public URL removal tool".
Webmaster Tools – My Removal Requests (Options selected for removing John Murga Forum):
Reason: Page has been removed or blocked from search engines
Removal Type: Outdated page removal
Note that only defunct web sites will be accepted for removal by "Google public URL removal tool". For obvious reasons the tool will automatically reject any functional web sites.
I see no advantage in having Puppy Linux users searching for help only to find broken links and non-existent web sites.