I'll agree that it would probably be more efficient to create a hash and work with that, however here is a way to get the array index using grep 
#!c:\perl\bin\perl.exe -w

use strict;

my @csvlist = qw(file3 file6 file1 file10 file5 file2 file7 file4 file
+9 file8);
my @listofnames = qw(file1 file2 file3 file4 file5);

for my $x(@listofnames)
{
    my ($test) = grep { $csvlist[$_] =~ /$x/} 0..$#csvlist;
    print "$x found at index: $test\n";
}

[download]
That is, if I understood your question correctly.

Update
Here is the output from the test script above: 

file1 found at index: 2
file2 found at index: 5
file3 found at index: 0
file4 found at index: 7
file5 found at index: 4

[download]
Update: diotalevi makes a good point below about the inefficient use of grep that I displayed above.

In reply to Re: Array searching, grep, first by ChrisR
in thread Array searching, grep, first by jimbus

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