Random

Hi
I have a spreadsheet that has a cloumn of names that varies in size each week. From that I need to randomly select a number of names depending on the sixe of the list.
They can not be duplicated. I have done =INDEX($B$2:$B$282,INT(RANDBETWEEN(2,282))) which does give names, but i think I need a macro for entering the size of the range and the number of results needed.Any help would be great. Thanks