Do I need to create a hash with the 6 names above before I can replace instances of JOE, FRED, and SAM, in a text file?
Yes, that is one way to do it. Give it a try.

Also note that you can simplifiy your code a little by eliminating qq around your variables: 

my $userlist = $ARGV[0];

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In reply to Re: How to replace strings in a file from a list? by toolic
in thread How to replace strings in a file from a list? by zBernie

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