I use one of those plastic coupon holders with the dividers. The receipt, price tag, and care card goes in the little Coach envelope that they put the receipt in. That then goes into a little plastic bag. I use small treat bags that I found at Target- they're flat and clear. I secure the bag closed with a removable sticker and attach a super sticky Post-it to the front with the name of the bag and other significant info like color and item #. Then I file these little packets in the plastic pouch alphabetically by line (Madison, Kristin, etc.) and alphabetically within each section by style. I do this for all bags, swingpacks, and large wallets.
For smaller items like wristlets I just keep one envelope (SLGs) with receipts, price tags, and care cards. I don't catalogue these.
For fobs I am not currently using I also bag these in tiny zip pouches with info on the outside. I keep these in a small coach box that a wristlet came in.
I don't know if this is the best way to do things but it works for me and I know exactly where to find everything. I'll probably have to adjust and move into larger organizers as my collection grows (and it will! LOL!!) It may seem like a lot of work but I LOVE doing stuff like this. Sorry, I am an ORGANIZING FANATIC!!!