Well, the v5 tutorials are more than 8 years old, so I'm not surprised that the scene files are hard to track down.
Anyway, a lot has changed since then -- not everything, obviously, but in many cases there are better tools and techniques available now (not to mention all of ICE).
There are some newer tutorials available on the Softimage Learning Channel: http://www.youtube.com/softimagehowtos. They don't cover the whole software yet, but it's growing.
You can find plenty more tutorials if you seearch the web. A good place to start is http://www.si-community.com/community/index.php, specifically the Tutorials and ICE Tutorials forums.