Stay away from illegal music sites. This is the first step to legally sharing music online. Stay away from illegal shareware or freeware sites. Along with providing music that is obtained illegally, you may find they have slipped spyware onto your computer when you downloaded their service. To know for sure if they have the legal right to the music they offer, read the fine print. Yes, all those little tiny words hidden in the User Agreement and located at the bottom of the web page that are in a very light color so you can only see them if you highlight them. You might discover that you need to remove some music sharing software if you want to share music legally.
Look at Jamendo, a music site that allows legal download and sharing of all their music. They do this by having what is called a Creative Commons License that allows them to have music from various artists and share it with you. In turn you can legally share this music with others. This site also shares 50 percent of advertising revenue to various artists that are a part of the RSP (Revenue Sharing Program).
Find a symbol called "Trustmark" on the sites where you are looking to download and share music files. This is a symbol that represents, to the Internet public, that the music available on the site is legal. A few of the services that have signed up include iTunes, We7 and Spotify. This is one more way to ensure that the music you share with others online is obtained and used legally. The bottom line is the artists worked hard to create the music you love and obtaining it illegally just so you don't have to pay for it is akin to stealing