accounts don't get linked, they are individuals for LL even if you have 5 signed up ( thats official the max amount of avatars per household, but never seen LL keeps you limited to that)
as far you want to get all your previous avatars, only when you signed them up with different email adresses you can find all yourself at a easy way, you can let the password recovery send a email with your name to the email you signed up with. But be aware... if you signed up with only one email adress... often only the last account will be remembered than
I think, if they want to help with this, your ticket will get the same route... you'll have to provide information about your sign up, they won't simply trust on your blue eyes and tell you avatar names.