On facebook: you go to settings, and then when that page opens, there's a link that says DEACTIVATE my ACCOUNT. Click on it, and BOOM! On Myspace: you go to my account, Account link, and then there's...
SO you go to settings - account setting- and it will say change click on that. and that will chaneg your name. It will take couple of weeks for the Facebook Authorities to confirm it. -Tina