Lake's YIM Status Message Puzzle

From ARG Guide/Trail Wiki

(NOTE: This page contains spoilers.)

<SLake> my status will lead you a bit further if you can add it to my site.

Lake leaves this status message on YIM (landau_luckman_lake):
0-385-51322-4 PG 216 Last Name
Which turns out to be the ISBN # for Dan Brown: The Da Vinci Code.

Bill looks at the hardcover version of the book and finds the last names on page 216 are Langdon, Teabing, Fache, and Faukman.

However, the ISBN # is for the US Edition - Paperback version of the book. As discussion about this appears on the Unfiction forum, a new status message by landau_luckman_lake appears on YIM. (0385513224=0375432302=0385504209)
All three are ISBN #s for "The Da Vinci Code"
0385513224 paperback.
0375432302 hardcover in large print
0385504209 hardcover
The equal signs suggest that they are all the same.

Another hint from Slake's status changes: " She always had a choice." >>>> Sophie's Choice. So the answer is centered around Sophie [Neveu]. The name, Sofie, also appears on page 216 of "The Da Vinci Code".

Another hint in #L3 by Slake... He talks about phone extensions and how he can't stand them. Telling us that there is no extension at the end of the site's address.

Sauceykat pulls it all together, and finds http://www.landau-luckman-lake.com/sophie. This gives us another puzzle... Sofie (http://deaddrop.us/awareguide/index.php/Sophie).