The best resource on the Internet is the newsgroup rec.audio.classical.recordings. Best way to find a recommendation for a particular piece is to try the google search on the newsgroup. There are some really knowledgeable people who post to that newsgroup and you can learn a lot by simply reading their comments.
Classical CD-guide in print or on web?
How do Audiogoners decide which recording to buy of a a classical music piece? I know there is the Good Classical CD Guide from British Grammophone magazine, but astheir customer service is awful, I haven't reveived it yet after ordering it three times. Are there other resources, maybe on the web, which compare recordings, and tell you which ones are the best?