Musical secrets!!!!!!!!!!!!!!!!!!!!!
Unfortunately, I know that no such reference material exists.
However, I can give you this secret of mine: music is an emotional expression, so when you are thinking about a song to see if it is valid, you think about the emotion that is portrayed in the song. Most music that is promoted today has emotions and feelings in it that are... crazy. You must be intensely critical about the music you listen to. Criticizing music is really an art in itself, there is so much out there that is harmful to people's minds. It is really quite dangerous because people willingly submit themselves to this destructive music.
Over time, however, the truth comes out and music that was once almost univerally liked is now seen for what it is- trash. But good music always withstands the test of time, it is universally liked and it always will be. Classical music is an example of this- it is still on the radio today.
That is about the best I can explain it, you just have to be intensely critical about music and then you will always listen to music that is superior and it will strengthen you. My favorites are the Beatles, Pink Floyd, Classical, Jazz, and Creedence Clearwater.
Again- be very careful, music can be very deceptive. Some music that you might think is a classic is actually bad- Santana is an example of this!
-Doug