Coin Lockers and Where to Find Them
Coin lockers are a near-ubiquitous oasis within Japanese cities and train stations for the multi-bag traveler.
I won't go on a long rant about how the US and other western countries could benefit transit riders greatly by providing this simple service. Not here, anyway. I'll just say that the car-brained mentality that those who are traveling will never need somewhere to store something for an hour or two is asinine. Then again, it's not like the US or Canada to really expect you to, y'know, go anywhere without a car. But I digress.
Coin lockers, or コインロッカー, do exactly what they say on the tin. They're cheap, plentiful luggage storage often found in train stations, airports, neighborhoods and side streets. They come in a variety of sizes, from just large enough to fit a backpack to large enough to fit up to two pieces of rolling luggage (or an egregiously large one). Some even take other forms of payment (namely, IC cards).
I'm not going to bore you with the intricacies of different types of coin lockers or post a tutorial on how to use them. That is left as an exercise to the reader.
What you came here for: How to Find a Coin Locker
I want to highlight Jun's blog, because it has been a fantastic resource for me. It's easy to find coin lockers while wandering, but for the longest time I had trouble trying to find reliable information about how many lockers were available at a particular station or how big they were. While the site is entirely in Japanese, it's packed with useful info and maps to coin lockers at most major stations in Japan, as well as many smaller ones. Definitely worth checking out if you're in need of a large locker.