>>Since they don't seem to sing in worship I don't think I'd make much of a Muslim....I probably wouldn't make much of a Friend either, for the same reason>>
Liland, Quakerism is a way of life, Islam is a way of life, music is a way of life, why would Muslims and Quakers not sing?
As IanB remarks above there is a Quaker songbook (I was a contributor myself!) We hear those songs whenever we choose to sing them.
By the way you left Inobu hanging rather uncomfortably in your other thread....