Well you could create  a new workbook  and actually populate it with Paste Special
/ Values.

Or you could simply lock the copy  down so that it will be read-only.

Not too sure what you mean by "linked formulas". Do you mean that they are
linked to another workbook that might change even after you made the copy? If
so, locking it down won't do the job, you need to remove the formulas with
copy/values.

However, if the formulas are simply referring to other cells in the same
workbook, then it's the cells without the formulas that you really need to lock
down. If they can't change, then the values  returned by the formulas won't
change.