I understand your pain. especially when you are upset over something, and if you even hint that your upset, the smug inhabitants of most "communities" will denounce you for being belligerent, and that's alright
who's right, I dunno, but I have been mad at shit and done the same exact thing on different forums.
now, it is generally accepted that it is impossible to get unbanned, wade fulp, the only mod who deals with this gets hundreds of un ban requests a day, and generally doesn't care. he posted a belligerant thread where he told these people to effectively "fuck off and stop messaging him"
your best bet is to think of a cool artist name/hook, and create a new account, specifically for music. design it all cool, make it fan friendly, and link to it from your newgrounds account. its a bit of extra effort, but if you wanna get serious about music, this is a good route to go.