Joining the group of people who have put their Workplace servers into the public domain, here is another URL: http://www.11tmr.com:9081/lwp/workplace/!ut/p/.cmd/PrepareEnrollment. I can't guarantee it will be around for very long, it's mainly there as a demo for next week but if you want to use it please feel free. The performance is also pretty poor as the machine only has 1.5gig of memory and a single hyper-threaded processor.
If my server isn't available then here are a few others you could try:
And Alan Lepofsky's tips on installation