I work at Best Buy and I noticed a few days ago that they put some new Lost stuff on the shelves. Apparently if you pre-order the sixth season you get this nice Lost Artifacts Book. It's a portion of the Lost Encyclopedia thats coming out later this year. It's free with the pre-order so I guess I'll be picking it up soon. It looks very, very well done.
http://www.fetts.net/2010/07/exclusive-lost-book-with-season-6-pre.html