from Diane Lee - I have actually two collections of stamps: foam mounted stamps such as Rubber Stampede Decor stamps and Chunky Stamps; and art stamps, mostly purchased as plates. I wanted a "catalog" I could easily carry with me when shopping so I used two blank books about 4 by 6 inches. I shop for the foam stamps usually at local stores and the art stamps usually online or at stamp conventions so I only need to carry one book at a time though both will fit in my purse.
The foam stamps are cataloged in themes such as "aquatic & marine life, plants and design elements." The themes are listed in the front of the book and each is "highlighted" with a different color. The edges of the pages for each theme's section are marked with the same color. The images are stamped in the book and a code for the stamp company is written next to each image. The stamps are sorted into the same themes and stored in pizza boxes.
For the art stamps, the companies that sell plates each have their own page(s). On the page is a list of the plate numbers or names, annotated with any stamps that are missing. I haven't gotten very far with stamping the images of the single stamps yet, but intend to do it pretty much the same way I have done the foam stamps. Since I rarely buy single stamps anymore, this seems less important to me. The art stamps are stored in plastic Spacemaker(TM) boxes, mostly by company. If I only have a few stamps from a company or don't know the company, the stamps are stored by theme. I bought a few wood mounted stamps and have been given a couple of dozen and they are just mixed in with the UM's.
I have used the computer to print the names of the ink pads I have, sorted by company, on white card stock and have put down a splotch of color from each pad next to the name. These color sample sheets are kept in the Iris cart with the stamp pads and I have only to look at them to see which color I want to use for a particular project.