use Find::Lib '../lib';

##</code><code>##

use Cwd            qw( abs_path );
use File::Basename qw( dirname );

use lib dirname(abs_path($0)).'/../lib';

##</code><code>##

$ find ! -type d -exec ls -l {} +
lrwxrwxrwx 1 eric users  8 Feb 22 17:04 ./a.pl -> bin/a.pl
-rwx------ 1 eric users 53 Feb 22 17:04 ./bin/a.pl
-rw------- 1 eric users 16 Feb 22 17:03 ./lib/Mod.pm

$ cat bin/a.pl
#!/usr/bin/env perl
use Find::Lib '../lib';
use Mod;

$ cat lib/Mod.pm
package Mod;
1;

$ bin/a.pl

$ a.pl
Can't locate Mod.pm in @INC (@INC contains: /home/eric/usr/perlbrew/perls/perl-5.12.2/lib/site_perl/5.12.2/i686-linux /home/eric/usr/perlbrew/perls/perl-5.12.2/lib/site_perl/5.12.2 /home/eric/usr/perlbrew/perls/perl-5.12.2/lib/5.12.2/i686-linux /home/eric/usr/perlbrew/perls/perl-5.12.2/lib/5.12.2 .) at ./a.pl line 3.
BEGIN failed--compilation aborted at ./a.pl line 3.