how do i do that??
i use @mac on my mail.appDid you have your account before the July 11 switchover? If so, is your email account "@me.com" or "@mac.com" getting spammed? If only one, give out the other to people and make a rule that anything going to the other gets filtered out.
It's called Apple ID, and no, you can not change it once registered (unless you don't mind abandoning your current Apple ID and registering a new one for another $99).