Do you mean "safe" as in the RIA will not find you and prosecute you for the illegal download of music or do you mean "safe" as in no spyware and virus's will be installed or downloaded?
Just because you look like an honest typer I will assume the latter. As you know, there are currently NO virus's, Spyware, Adware, Malware, etc. for the Mac OS X. This is because it is a more secure system than Windoze will ever hope to be. That does not mean that you are completely safe. There are still idiots out there who write small AppleScripts that, when run with your permission, will take away your Documents folder. With that in mind, take a look at Limewire. It works reasonably well and has none of the idiotware that Kaazaa is famous for.
Is there any possible safe free music downloading for mas os x? I use to have XP and had trusty files but that only works for windows.