What is the name of this song from the Funimation Dub of DBZ? The song is played often when Frieza is doing evil things. I found a compilation that contains it at the given time code here.
That song is the SoundTrack 7 of DragonBall Z.

You can hear it here. 

And for more of the DragonBall Z soundtrack album here you have a full playlist with all of them.