>I am looking for a pair of earplugs that block out as much noise as possible.

Slate.com had a review of earplugs recently:

http://slate.com/id/2118800

As an earplug user, what I think is crucial is correct insertion. For example, when I'm on a flight I see a lot of people just "cramming" the foam plugs in their ears, as opposed to rolling them into a compressed cylinder, pulling on the ear, and placing them deep down into the ear canal. Makes a HUGE difference.