Where to find hi-quality CD's of classical music

Season's Greeting, One and All,

I'm a lover of classical music and would like to find a source, on the internet (and/or elsewhere) to purchase hi-quality classical CD's. I live in Tucson, AZ - a nice place to live, but somewhat lacking in venues to satisfy my classical music interests. So, I ask you: Would you, perchance, be able to point me towards a site, store, source, where I could purchase what I call hi-quality CD's, meaning, music recorded with hi-fidelity, and quality recording standards as the goal. If memory serves me, I sort of recall reading somewhere that one could tell if a CD was a quality recording by some type of symbol or code on the jewel box label or on the CD itself. Does anyone know if there's any truth to that? Any and all input would be much appreciated.

georgester