There are many ways to find out about specific recordings, but word of mouth is the best. A close second best is reviews. A close friend recommended some of his favorite sources:
The bulk comes from reading online. I read reviews such as the ones here:
along with forums:
I mostly use this to determine which masterings/versions sound the best after finding something I am interested in.
I have signed up for the newsletters from two stores that specialize in audiophile things, to keep abreast of the new releases: