what you do is get a mic... and put it next to the computer speaker. Press play on the myspace simultaneously press record on the program of your choice. Save it in .WAV. Then download a program that can convert .Wav to .Mp3
I haven't used it much but try MP3 Gopher. http://code.google.com/p/mp3-gopher/downloads/list
You just gotta get the artist's friend ID, type it into Gopher and it'll give you a list of the songs on their page.