I have a Vinotheque 550 wine cellar, which (despite its name) holds about 450 bottles. That's with one column of magnum racking. I love being able to keep my wine at a constant 55 degrees F; my only real frustration with it is that the racks are suited for the typical Bordeaux-sized bottles, so I have trouble stowing my fatter Pinot Noirs, Syrahs, Turley Zinfandels, and champagnes (lower case "c" to indicate I'm being casual with the term, using it for sparkling wines from outside Champagne as well as true Champagnes).
Within the cellar, the basic organization is by type and year within type. I drink almost exclusively red wine, although I have some whites on hand for company--Chardonnay for my father, Sauvignon Blanc since I think it's generally tastier, and a few bottles of (on the dry side) Gerwurztraminer because it can work well with curries. White wines are relegated to the far left column of the cellar.
The space beneath the racking holds a surprising number of bottles, and right now it's full of Turley Zins, Erath Pinots, and a couple of Schramsberg sparkling wines. The magnum rack (on the far right) has six actual magnums (3 of them are Cabernet Sauvignons from 1987, my nephew's birth year, which I am trying very hard to retain) and I've jammed in Turleys in the rest of the space.
I have my list in a spreadsheet, with headings "Bottles" (quantity), "Size" (375ml, 500ml, 750ml, and 1.5L), "Wine" (winery, location, vineyard, and varietal), and "Area" (where the wines are within the cellar). And I see I was clever enough to add a comment to the Area cell in case I forgot how I set it up:
M = magnum column
B = bottom (under racks)
1 - 12 start from the right (first column to the left of M)
M starts from the bottom up; B goes right to left on the bottom, then left to right on the top.
1 - 12 start from the top down.
I'm a bit of a geek in general, I suppose, wine- and otherwise.
In theory, I update a printout of the spreadsheet when I remove or add a bottle, and update the actual spreadsheet on my computer from time to time. In practice, that works nicely until I either get a large infusion of new wines or get a little carried away entertaining. At some point, I have to do a full physical inventory, which is quite a production. However, even if I were absolutely anal about keeping track (I used to be really hardcore), I'd still need to reshuffle the wines from time to time, since they're in by year within varietal--so when newer wines arrive, the spaces where the older wines were are the available spots.
My categories are a little loose--other than the mixture of fat-bottomed bottles
below and in the magnum section--it goes (right to left) Pinot Noir, Syrah, Petite Syrah, Zinfandel, Petit Verdot (okay, I only have one bottle of that!), Malbec, Cabernet Sauvignon (which includes Bordeaux and California Meritages), Merlot, Cabernet Franc, Port, and that takes us to the column of whites. Why don't I just stick the other Bordeaux varietals in with the Cabernet Sauvignon, Bordeaux, and Meritage? Good question, as I waffle on it from time to time, but I think my feeling is that I'll cellar the latter longer, and they're typically more expensive, so I'll open the Merlots, etc. for people who aren't as picky about what they imbibe.
There are a few extraneous bottles--sparkling wine and white wine in the refrigerator, and some drink-anytime reds in the coat closet, but I don't count those in my spreadsheet. Once a wine exits the cellar, I consider it gone.
All this because a friend of mine asked my advice on purchasing a small wine cooling unit--to hold maybe two cases--and I figured there might be some opinions here.