The pages to hold the dies are made from magnetic sheets - I found magnetic dry wipe boards, first from Home Bargains, but now my branch has run out, I'm using these from The Works. Each board will make two pages with a large chunk (technical term) left over. I save the pen holders for future projects (you never know!) and my husband uses the pens for work so nothing is wasted!!
At first my plan was to just bind the magnetic sheets together as they were, but then I thought they'd be more secure if they were inside something, so I bought some CD sleeves which cost about £1.99 for 50 at Wilkinsons. To stabilise the sleeves and to provide a strong place to punch my binding holes, I use acetate - for this I use packaging acetate from boxes and such, like the dies themselves are sold in. I stick the acetate to the sleeves with extra sticky tape (the red one) I ran out today, so I've had to use regular double sided.
My covers are art board off cuts, covered with designer paper, and I bind it all together with BIA wires then add my magnetic pages and dies. I store the books flat to reduce strain on the binding.
So far I've made 6 of these - two for Spellbinders dies, one for Nellies & xcut, one for Marianne's, a longer one for longer label dies and one to keep my coloured images ready for making into cards. It's a system that works really well for me; my dies are organised and well kept as well as being accessible.
Thanks for looking.