How much easier do you want it :)

#! perl -slw
use strict;
use Win32::Process::Info;

print "My pid: $$";

my $pi = Win32::Process::Info->new;

my @info = $pi->GetProcInfo();

my @procsOfInterest = grep{ $_->{Name} eq $ARGV[ 0 ] } @info;

if( @procsOfInterest ) {
    print "A process with the name $ARGV[ 0 ] was found with pid:",
        $_->{ProcessId}
        for @procsOfInterest;
} else {
    print "No process with the name $ARGV[ 0 ] was found";
}

__END__
P:\test>381203 perl.exe
My pid: 1184
A process with the name perl.exe was found with pid:1184

P:\test>start /b perl -le"sleep 60; print 'Bye'"

P:\test>381203 perl.exe
My pid: 340
A process with the name perl.exe was found with pid:1600
A process with the name perl.exe was found with pid:340
[download]

Righteous! sometimes the most obvious & simple solutions stand before us jumping up and down saying:
'see me how obvious am I!!'
Thanks for sharing your wisdom!