From Val - I have a storage tip that has worked great for my stamps. I have bought 3 5-drawer bins on rollers from K-Mart that are overflowing with stamps! The first 4 drawers are thin, perfect for stamps, easy to access and see them all! The bottom drawer is much larger, great for ink/brayers/mounting supplies, etc. They are usually $19.95 and are well worth it!
From: Tamra - Stamp Storage Cabinet - I made something in cabinets for storing my stamps. We have those oak cabinets from Home Depot and one of the things I love about them is there are 'pantry' units to match them. They come with drawers inside. So I bought a bunch of extra drawer slides, some of the 4X4 pieces of 1/4-inch plywood and some nice corner molding (like an L). I cut the plywood to the size of the pantry drawers I had, spray painted them to match the counter tops to meet my coordination requirements. .
Then cut molding pieces the length of the front and back of the plywood, sprayed stain on the molding to match the cabinets. Basically, I have a flat sheet on drawer slides. I mounted them in the holes for the adjustable pantry drawers, every 4 inches or so apart. The lip in the front matches the cabinet and serves as a way to grab the drawer and pull it open. Since it is on real drawer slides, the sheet won't fall and I can pull it out and browse the stamps without having to support them or lift them. That's nice and very handy, since sometimes I just look at them for fun to admire their beauty! .
I have since gone back and added more of these drawers and spaced them as close together as I could and have clearance to pull them all open. I have them grouped by themes, but also by mount thickness. Those Magenta stamps are so much thicker than others! I also have those 'behind the door' stamp cabinets that are so great. Mine are behind French doors, so I painted them the same color as the wall and hung framed things on them and they blend right in with the rest of the wall.