Music Software?

Does anyone know of any good software that I can use for taking out instruments in music? Like I need to separate the songs up so I can hear the bass parts in them so I can play. I know the songs, I just need to be able to hear the bass. I'm deaf in an ear so it's really hard for me to pick out the different parts and just be able to focus on the bass. Does anyone know of software that I can use to edit that? So that maybe I can turn down the volume of the other instruments/singing so that I can listen to the bass line inside the song? It'd be really helpful if you did.

My band wants me to learn some songs but I don't know what the bass line is so I don't know if I'm playing it correctly. That'd be amazing. =]

Thank you!

Annie