Um, not wishing to seem a stickler here, but this last idea sounds very much like piracy to me- if you're listening to something on Spotify, the rights holder gets paid each time you stream the track (a pittance, but still...) if you're downloading the song in a way they don't wish you to do, there will be no record of how much you play the song from that download. Unless you own the phonorecording copyright (the circled P symbol) and the Song copyright if it's not traditional, you should just bite the bullet and pay the 99 cents for a legal download.
    Respectfully,
Kristoffer