foreach (@first_file) { #get data from first file
    /\b(\w+)\b(.*)/; #split the first record, by name and data
    ($key, $data) = ($1, $2); #put thoose into scalars
    foreach (@second_file) { #next file foreach line in first file
        /\b(\w+)\b(.*)/; #run through same regex and get keys again
        if ($1 eq $key) { #compare keys from both files
            $merge{$1} = "$data$2"; #if they match, merge into hash
        }
    }
}
[download]

while(<FIRSTFILE>) {
 ($key, $rest) = split;
 $list{$key}= $rest;
}
while(<SECONDFILE>) {
 ($key, $rest) = split;
 $list{$key}.= " " .$rest;
  
}
for(sort keys %list) {
  print "$_\n";
}
[download]

To get all of the data, you'd do a SQL JOIN command on the name fields. It might end up something like 'SELECT * FROM location, instrument JOIN ON location.name = instrument.name'. (Untested and off the top of my head.)

If you'll be doing this sort of thing often, I would highly recommend a relational database, like MySQL or PostgreSQL. If you're looking for a way of doing the same thing without a real database, DBD::RAM is a pretty cool module that'll simulate it for you.

That said, fundflow's example is an easy simple hack (in a good way), that will do only what you've described and nothing more.

I wouldn't bother trying to hack in more complexity, though, as this is a case where there's an excellent, flexible, already-coded solution. (Besides that, learning a bit about SQL and DBI will make you a more valuable programmer.)