what axl rose does with his voice is called 'pinched falsetto' where he sings with an artificially-raised sounding pitch (not his normal range) and then he tightens it a bit (pinch) that makes it kinda sound like mickey mouse. it hurts if you try singing like this for a whole song so don't try this without practice and proper knowledge... i had swollen throat for a week coz of imitating him!