1.--Allah says in the Qur'an, (what translated means), "And of mankind he who purchases idle talks to mislead (people) from the Path of Allah without knowledge, and takes it (the Path of Allah) by way of mockery, For such there will be a humiliating torment. [3 1:6].
Al-Wahidi, along with other scholars of Tafsir (explaining the Quran), said that "Idle Talk" in this verse ('ayah') is singing. The following companions gave this Tafsir: Ibn Abbas, Ibn Masud, Mujahid and Ikrimah. Ibn Masud said, "By Allah, whom there is no God except Him, idle talk is singing."
2 -- The Prophet said, what translated means, "From among my nation, there will be people who will render as lawful adultery, weaving silk (for men), Al-Khamr (liquor) and AlMaa'azif (musical instruments)." [Al-Bukhari].
This Hadith states that musical instruments are Haram, and there is no disagreement among the scholars on this. In his book, Ighathat Al-Lahfan, Ibn Al-Qayyim said, "When the Prophet said, 'render as lawful,' he meant that it was unlawful, then the people made it lawful."
There is a difference of opinion amongst scholars. The voice is the main 'medium' - music comes second. I am sure you have heard the melody used to give the call to prayer and during recitation of the Qur'an. Instruments are unlawful, but some say it is unlawful to use drums too - some say drums are ok because when there was a wedding at the time of the Prophet, someone would sound out a drum in the area. There are a number of Islamic 'songs' you can take a listen to if you want. Do you know Cat Stevens? The 70's popstar who became a muslim? Well, he uses his voice to sing about Allah and Islamic faith now - doesnt really use instruments except for a drum sometimes. Also there is a guy who is Canadian - he became muslim a while back and he's very famous in the muslim world for his 'songs' ('An-nasheed').
http://www.load-islam.com/C/Media/Dawud_Wharnsby_Ali/ listen to his nasheed here.
Some other nasheed artists are here - take a peek.
http://www.load-islam.com/Media/
Im sorry if I have been too vague.
Peace