Advance Search Link?

I would also appreciate the ability to link a page with the advanced search uncollapsed.

Workaround:

I used the JS Injector module to add this JS to any pages matching "search*" url:

//wait until the rest of the jQuery has been loaded
$(document).ready(function() {
  //break apart url to get anchor
  var url = document.location.toString();
  if (url.match('#')) {
    var anchor = '#' + url.split('#')[1];
  }   
 
  //click collapsed fieldset to expand
  if (anchor == '#advanced-search'){
    $('.search-advanced legend').find('a').click();
  }
});

Just create link to "/search#advanced-search"

Is this still the best (only?) way to have a stand-alone "Advanced Search" page? You basically have to trick the advanced tab to be revealed by injecting javascript?

This is an old issue. I'm marking it fixed but if you disagree, please update and provide additional information.

To add an advanced search link to the basic search box, make a copy of search-block-form.tpl.php (from the core search module) and put it in with the template files for your theme. Edit it to add:

<div id="adv_search_link"><a href="/search">Advanced Search</a></div>

right before the closing lines:

  <?php } ?>
</div>

Now rebuild your theme registry (there are several ways of doing this - the Flush Caches submenu in the Admin Menu module is the easiest), and voila. You can use the #adv_search_link ID to add styling in your theme's CSS if you like.

It would be nice if this module had that as an option that could be turned on and off, though, for those who may not be comfortable editing template files (though this is a pretty easy edit).

Patches are welcome to add this feature…
I'm busy updating the module to D8.

I just still miss this feature too. It would be really great to have an option to have the link to advanced search on default search block.

Unfortunatelly I cant open it again, so I have to create a new one for drupal 8.x ...