I have a related problem. I used my normal iTunes id for iCloud. But now I want to change it to an @me address to keep iCloud data separate from the wife and kids.
So I was fooling around with iCloud and turned on syncing notes. It wanted an @me address to do so. So I figured it was the perfect time to create it. I went ahead and got the email address I wanted, then it was done. It never let me choose a password. Now I'm stuck with the @me address I want and no way to access it since it never had me pick a password.
Any clues what to do at this point?