#!/usr/bin/perl

use strict;
use warnings;
use utf8;

use YAML;
use WebService::Simple;

my $key = 'hoge';

my $service = WebService::Simple->new(
    base_url => 'http://maps.google.com/maps/',
    param => {
        key => $key,
        output => 'xml',
    },
);

my $res = $service->get('geo', {q => '東京都千代田区千代田1-1'})->parse_response;
warn Dump $res;

↓こうなった。

        - Response:
  Placemark:
    AddressDetails:
      Accuracy: 8
      Country:
        AdministrativeArea:
          AdministrativeAreaName: Tokyo
          Locality:
            DependentLocality:
              DependentLocalityName: 千代田
              Thoroughfare:
                ThoroughfareName: １−１
            LocalityName: 千代田区
        CountryName: Japan
        CountryNameCode: JP
      xmlns: urn:oasis:names:tc:ciq:xsdschema:xAL:2.0
    ExtendedData:
      LatLonBox:
        east: 139.7571208
        north: 35.6869988
        south: 35.6807036
        west: 139.7508256
    Point:
      coordinates: '139.7539732,35.6838512,0'
    address: '１ １千代田, 千代田区Tokyo, Japan'
    id: p1
  Status:
    code: 200
    request: geocode
  name: 東京都千代田区千代田1-1
xmlns: http://earth.google.com/kml/2.0

あれ。api keyいらんのかな。