I just got the Bose QC 20 noise canceling ear buds. I've had these for less than a week, but they have the ability to block 95% of all background noise.
I got these because my work environment has changed recently and I now have 2 people sitting outside my office and I can’t play my stereo and I didn’t want to hear their conversations.
With these in I hear just about nothing going on around me. Luckily I can still hear my desk phone ring with the ringer volume all of the way up.
They are $300.00, but worth the investment to me.
Good luck.