I like Pandora and Spotify. I can't get either in Mexico, so when I'm in Mexico I use Grooveshark - which doesn't really do music reccomendation but allows you to make your own playlist.
I use skullcandy earbuds for my ipod. On the PC, I use razer carcharias headphones and I love them. Super comfortable for over-the-ear and the sound is really good for a decent price. I think you could get the same quality for cheaper, though - I bought them because I wanted the attached microphone.