If you haven't already, look at help for RANDOMIZE. Also, I've found
some very good (and free) add-ins from NumTech (specifically NtRand)
if you wish to create something from scratch. However, like the
Christmas song this has been done "many times, many ways". Do a
Google search on "Return random numbers using VBA in Microsoft Excel"
and look at the first hit. There is code to generate unique random
#'s you can cut, paste, and modify.

Regards,
Steve Hieb