How do you find BEST classical recordings???

I recommend National Public Radio (NPR) Performance Today book called "The Basic Record Library". It has over 800 listings with catalog numbers. It is available online for only $10 at this link...
http://shop.npr.org/catalog/Product.jhtml?CATID=8&PRODID=78


Online they have a list of 50 essential recordings. They are up to 39 so far, so you can check back each week. The whole list so far is at this link...
http://www.npr.org/programs/pt/features/pt50.html

Pls1 - I have to chime in to thank you along with all the others for the answer to my question. By the way, has anyone used AMG online?

Being a classical music "nut" myself, I dare say Pls1's post is a reference. I second his comments on the Penguin, Gramophone & Fanfare guides on all points & one more: esp. on Penguin, I find inconsistencies in the recommendations. OTOH, older Gramophones' notes are a reference.
Again, www.classicaldigest.com is a good source.
I can add:
The Diapason guide (in French) was very good, and more consistent, and it also mentioned vinyl -- but the last issues, late '80s, are dated and difficult to find.

Another resource to check out is Andante.com. The have a huge reference base of info about classical music including program notes for most standard pieces, a comprehensive timeline, composer profiles, the short Grove Dictionary of music and much more. Andante also is the source on the web for Concertgebouw, Philadelphia, London Symphony and Vienna Phil concerts on demand. They also have a streaming audio channel that has the widest range of classical music (medieval to contemporary and 1920’s to newly released recordings) in excellent interpretations. They cost about $10 per month and you will need a high speed Internet connection to listen to the music. Listening to the Andante web channel for a few weeks will give you a good idea about what you like or dislike. They are in negotiations for a major collection of reviews but that will take some time.

The allmusic.com guides are excellent quick references to works and performers but they won’t help too much in deciding which performance to buy. Classical.net is another resource but their recommendations place heavy emphasis on availability of the CDs. They often do not recommend any of what I would consider the “Top 5” performances, but all their recommendations are decent.

BTW Peter what are your current favorite performers, composers?

Also, check out ClassicsToday.com