NTE is the brand carried by Fry's Electronics here in the Western US. All their parts start with NTE (op amps, etc.) Go here and search and you will find mostly NTE parts:
http://www.frys.com/There is also their web site:
http://www.ntepartsdirect.com/Not cheap, though.
BTW: Rocket - I suggested that we officially have a thread like this a long time ago but it never took off, so I long ago took that to be a sign that getting original parts is usually the best idea - however, there are always exceptions and I believe it is VERY circuit dependent.
So, while we are on the subject, here is a similar one that I have relied upon quite a lot:
http://www.talkingelectronics.com/ChipDataEbook-1d/html/OpAmpList.html - all of the most common opamps