Good quality cd's

Being retired and started to listen to more music, I have a nice but modest system. One thing I have noticed is that when buting cd's there is a lot of stuff out there and none of the sites really devote much space to the quality of the cd. I know there is xrcd,sacd,hdcd, and redbood which may all go by the wayside. One thing I have found out is with a good system a good cd will sound great and a bad cd will sound terrible.
Are there any sites out there (Amazon do a real good job)have give a little space to how good the cd may be; mixing, using good equipment just producing a good quality cd.
Would appreciate any advice.