I apologize for question 1; a different query turned up the 10.6 tool:
I'm hoping someone can tell me if these tools will happily run on a non-server edition of Mac OS 10.6.
The Server Tools you can download from Apple will install and run on OS X client, but they will only connect to and monitor OS X Server boxes.
So that won't get you where you want.
One command that will help you here - and which is present on OS X Server and OS X client - is dscl.
dscl . list /users
Or a web search, etc...