If my workspace is set up for a project containing many sub-projects. If I want to get files for one of the sub-projects, all I do is "cd" into the appropriate directory and invoke the get command, correct
What if I just a copy of the source for the sub-project in another location What do I do Do I create another workspace at the sub-project level

Question about Workspace in command line
Shirvo
"Tf get" is "update my entire workspace".
To get "from this directory on down", I use "tf get * /r" - don't know if that differs from "tf get . /r" or not.
Like Richard, I'm not sure what you're asking in your 2nd question, but if we didn't cover it, please elaborate and we'll try to help you out.
Thiago Tota
I'm not sure I follow the 2nd question. Depending on what you're trying to do, you might want either a 2nd workspace or a branch.