The someone else can contact the Billing team through the web site (http://support.lineage2.com) or by phone, and the team should be able to assist with retrieving that information. :)
If you can give them the CD key and whatever billing information was on the account, they give you the password and account with essentially no more questions asked. Far faster response than we've come to expect from NCSoft too.
It's 222-2222
I got an answering machine that can talk to you
It goes
POS:
Hey how ya doin'
Sorry ya can't get through
Why don't you leave your name and your number
And I'll get back to you