LWP::UserAgent doesn't parse content. WWW::Mechanize does.

$ cat ./langley
#!/usr/bin/perl
use strict;
use WWW::Mechanize;
my $browser = WWW::Mechanize->new( autocheck=>1 );
$browser->get('http://www.google.com');
$browser->submit_form(
    form_name => 'f',
    fields => {
        q => 'langley public library',
    },
);
my @links = $browser->links();
for my $link ( @links ) {
    my $abs = $link->url_abs;
    next if $abs =~ m[^http://.+google\.com/]; # Google links
    next if $abs =~ m[^http://\Q64.233.167.104/]; # Cache
    print $link->text, "\n\t", $link->url, "\n";
}


$ ./langley
Fraser Valley Regional Library
        http://www.fvrl.bc.ca/comm_branch_langleycity.asp
Sno-Isle Libraries
        http://www.sno-isle.org/
Public Visitor's Page for NASA Langley Technical Library
        http://library.larc.nasa.gov/Public/
Notice for NASA Langley Employees visiting the Technical Library ...
        http://library.larc.nasa.gov/Public/nasalangley.htm
Canadian library Web sites and catalogues by region: British ...
        http://www.collectionscanada.ca/gateway/s22-221-e.html
LANGLEY PUBLIC LIBRARY in LANGLEY, Oklahoma Library Data / Profile
        http://www.librarybug.org/library-OK0111.html
1st Services Squadron - Langley Air Force Base, Virginia
        http://www.langley.af.mil/1msg/1svs/Library.shtml
Public Libraries, Oklahoma (Books)
        http://www.ohwy.com/ok/l/library.htm
Library - Langley High School
        http://www.fcps.k12.va.us/LangleyHS/library/
Kings Langley Public School Library
        http://members.ozemail.com.au/~stewil/fivew.html
[download]

All the other caveats about Google not liking scraping still applies. Please also take a look into Spidering Hacks by Kevin Hemenway and Tara Calishain.