For your first question:

my( %site, %search );
use SiteConfig ( site=>\%site, search=>\%search );
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Update: Rereading your code, I suspect the above may not be enough information. (:

package SiteConfig;

use strict;
use XML::Simple;

sub import {
    my %toImport= @_;
    foreach my $key (  keys %toImport  ) {
        %{ $toImport{$key} }= %{ XMLin("./$key.xml") };
    }
}

1;
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        - tye (but my friends call me "Tye")