Is there a real legit way to download free music into your iphone?

I did limewire but alas! Forstwire doesn't work on my computer, i don't know.one of my brother's friends has about 900 songs in their itunes icon on their phone and they did it for free.how? Please share?

IPhone/iPod/iPad users can get iTunes and Amazon gift codes for free!

1. Open up Safari on your iDevice and go to tinyurl.com/itunes4ever
2. Install an app and keep it open for 30 seconds.
3. Receive your iTunes or Amazon gift code