I have recently configured LinkedIn in such way that I no longer receive any recruiter spam. The trick is to deny the "direct" messages from people outside of your network and also require a connect requestor to know your email. These two simple things (plus opting out of any of LinkedIn's mailing lists etc.) and boom! - serenity.
Next to the search bar, there's a little button that says "advanced" that I believe will still allow you to get to the functionality you're looking for in a less intuitive way.