How can you send music from a PC to additional rooms of a house which do not have PC's?
My PC's soundcard is connected to an auxiliary jack on my stereo, rather than the PC speakers.
Ask at a computer store; they can help you out with cables/wiring, etc.
If it is music you have created yourself then you can send it to anyone. If it is music created by someone else that you have purchased (or acquired otherwise) then it is illegal for you to send it to someone and for anyone else to receive it unless you actually own the copyright and distribution rights for the music.
If you want to upload songs on your phone you need a cable that probably came with your phone you plug it into you phone and the other end in the computer then just upload music, but if your asking how to send music when you are sending a text message you click menu and add music pick a song then send it