I have also been gathering materials for the book. Mostly the pages will be like the LTCs with more embellishment and on a larger scale. A lot of the collage materials, ephemera, etc. I already had. Organizing everything so that I can plan layouts has been the major challenge. This is one solution I have come up with:

Keeping track of all the little pieces is also hard, so I am trying plastic baggies this time around. We'll see how it goes.
I forgot to mention - an early stage of the book is covering it. I wanted a look of something tough but well traveled, so I got a leather coat at Goodwill, cut it up, and used the largest piece to cover the book. It has quite a nice look as a result. I also used some Tim Holz brass corner embellishments to be corner protectors.

The Suitcase Project, aka Altered Book, aka A Home for my LTC Stamps

So I have a lot of stamps that I've carved for making LTCs, but they are my best carvings and I'm not willing to plant them. However, they just sit in an old Walker Shortbread tin doing nothing otherwise. Therefore! I am making an altered book that will travel in a wood suitcase to Letterboxing gatherings with me.

I will chronicle the process here...

I made the suitcase about a year ago.

It is a wooden suitcase styled box from the Redmond Ben Franklin. I got sticker paper from Stampdoodle in Bellingham and printed vintage travel labels (I love Google Images!) on my ink jet. After I painted the box and stuck labels all over, I made a BIG MISTAKE. I wanted to seal the whole thing and used Mod Podge, painting it on. Well, it lifted the ink and smeared it around somewhat. As you can tell, it wasn't so bad, it maybe even aged the look a bit, but I panicked a bit there.
So the book itself is, yes, a Physics textbook. St. Vincent dePaul and Goodwill are great sources for cheap books. I usually shop purely based on size of the book (this one needed to be big). I think this one was about a dollar or two. Bonus is the cool text with formulas and charts and such. I'll have to find ways to integrate some of the book's original pages into my overall design.