Bismillah, Wa Salam Alaykum The best guidance is the guidance of Muhammad, so if my words are in contradiction to it, then disregard them! And if you dont Im free of your actions!
Erm, I know a brother who used to wake up and put music on, so as he changed and get ready all he would hear is music.
He'd listen to it on his way to school, and way back, and spend time in class writing songs. Then this brother became Muslim.
He still struggled, I mean, depending on what you are like music effects you in different ways, some people 'listen' to music, others just 'hear' music, one is attached closely to the figures he listens to and the other is not that much, he may like them but not that attached to the point that they are like parental figures to him. So it depends on who you are.
Anyhow, this brother was actually making songs and so forth in school, and towards the time of becoming Muslim he was really into it.
But, as he approached Islam, he found himself, instead of listening to a tape of music in the morning, he would put on a speaker, to the point that he memorised parts of the talk on the tape before becoming Muslim! Trust I tested him lol.
After becoming Muslim he still had problems, first he heard people say it was halal and others haram and so forth, so here are the steps:
1. Find out the ruling clearly, the cure for doubt is knowledge. The brother found out the evidences, so as to leave no doubt. So later on when shaytan wisphered to him, he could not say 'Oh maybe it is halal let me listen cos some say its halal'. No! Rather he found out the clear ruling leaving no doubt!
2. Took steps towards changing, tried to delete the music he had, and the music he was making. He didn't go to the websites his music friends were on because he knew he would be tempted to make songs.
3. He kept busy.
4. He understood that the body sometimes is lazy and can't listen to Qur'an, especially if you dont know arabic, for hours and hours, I dont think theres a shame in that, for even those better than use take breaks! So he would take breaks so not to wear himself out, and listen to Poetry, real islamic poetry, not 'Allahu Alllahu Alllahu...' or 'He Was Muhammad, Sallahu Alayhi Wa Salaaaaaaaaaaaaaam..Muhammad Mercy of All Mankind, Teacher of All Mankind, OHHHHHHHH Habibi Muhammad' none of that, but pure poetry, listen to Bayquniyyah, listen to Nuniyyah, listen to `Ishrat ul-Ikhwaan'. Some may think that is extreme, but you know what, when you listen to 4 shaved singers looking like pop stars sining songs with beatboxing and so forth, that's just going to aid you to move back to your old self, well tahts what the brother found. So when your singing to 'Make dua, when you feel somethings wrong, Make dua, OHHHHHHHH OHHHHH OHHH OHHH, Make dua, Its hard, to see, brothers and sisters suffering...' and that stuff, you'll only fall back and you'll find yourself soon singing 'Tonight...Ill be your naughty Girl...tell all your boys' trust, I remember in my Christian Union a preacher asking how people praise God with such words lol, its true.
Anyhow I think thats about it. Should keep the keen reader busy.
. It all started when i got down to deen and when my Aalimah gave me a big lecture on how i will get there in Janah rather listening to horrid music...
Still haven't completely ''left'' music perse, because it is virtually everywhere, but as a Muslim I feel that it is my duty to not listen to music. Like others have said, if you have the urge to listen to music because you own an mp3 device or an IPOD, then utilize it in a way that will assist you in becoming closer to Allah and being an overall good Muslim. Add some lectures, surahs, and maybe some nasheeds as well. Also, make sure that when you're on the computer that you have bookmarks left for you to watch some good lectures. 
wa alekum alsalaam