The program Limewire is rly good for other songs but it's not the best for animé and jpop. If you're looking for anime, I'd strongly recommend Gendou's animé musique ^^ link If toi want jpop as well, toi can check out link It also has quite a few animé songs and it's rly awesome too :) Both websites require sign up but I can definitely say it's absolutely worth signing up for either of them, especially Gendou ;) Hope this helps :D
link is a site just for mp3 anime, if toi rejoindre the site and can make as many downloads toi want, is a Brazilian site, so it's in Portuguese, but just as toi do the chercher par putting the name of the animé at the bar, not must be hard for anyone not understand the language x3