We have rigged up a temporary link to the old download page
http://www.hostingseries37.net/~SimSig/html/downloads.html
No gaurantees it'll work, it may need some fiddling with so good luck.
John has written soime instructions
http://www.SimSig.co.uk/index.php?option=com_agora&task=topic&id=5&p=3&Itemid=54#p343
and they do work because I've just managed to download one of the Sims.
UPDATE 9/11/09
Links to all the sims can now be found on the WIKI
http://www.SimSig.co.uk/dokuwiki/doku.php?id=andysandpit:usertrack:ssinstall:download
Note this link is liable to change without warning as the WIKI is redeveloped.
Peter