You mean the scripts we have on the repository? Or the scripts under the quest menu in mafia?
If you mean ours, you will have to register to download the scripts (there are links at the end of the original posts - usually). ( BTW, Guests have access to attachments, unless I screwed up somewhere, in which case let me know - but I just tested it... -Daychilde ;D )
Then move them to your Scripts folder (it is in the same folder wherever you have mafia.) And then while running mafia, look under the scripts menu.
If that isn't clear enough, someone else will have to fill you in until I get back from work in about 10ish hours...