I don't know of any way to create a clickable link in a shell.

Maybe as an alternative, you could provide a command a user can hit to open up a browser to a google search. For instance, this works on my MS-Windows box:

use strict;
use warnings;

my $buck;
print "does your rock have the same metalic luster as gold? yes or no:
+ ";
chomp($buck = <STDIN>);
if ($buck eq 'yes')
{
  print "your rock is pyrite [Hit enter to quit, \"L\" and enter to se
+arch Google] ";
  system('explorer "http://www.google.com/search?q=pyrite"')
    if (my $in = <STDIN> =~ /^L/i);
}
[download]

By the way, your 3rd line of code has a typo: if ($sbuck eq 'yes') should be if ($buck eq 'yes'). You would have caught this typo if you had started your script with use strict;, which is almost always a very good idea. In addition, your second test is using the variable $buck instead of $buck2 (line 11).