After going through the Disk Union punk store in Shinjuku, it was only a short walk (after a brief stop at the giant Godzilla statue) to Warehouse & Nat records. Now, I can't say that I completely understand how there are two record shops in one store and to be honest, I wasn't really paying a ton of attention to that when I was in there. But essentially, Nat records specializes in noisy rock and roll and Warehouse seems to focus on used stuff. Exactly where one store ends and the other begins isn't something that I took a picture of, I guess.
No matter which store is which, Warehouse/Nat was a great place to dig. Lots of 7"s, lots of punk rock and a good amount of interesting older records to peruse (you should see the Ventures 7" section at this place).
I bought a lot of 7"s while shopping here. I don't think I picked up any CDs and unfortunately I don't really remember if I bought any LPs, but I would think I grabbed at least one. As the trip gets further and further in the rearview, I'm having a more difficult time remembering exactly what records I bought in each store.
Warehouse/Nat is definitely a shop worth hitting up if you're in Tokyo. It doesn't have quite as much foot traffic as the Disk Union stores, but they have a lot of hidden gems here. If you are into some serious digging, you could probably spend quite a long time pouring over their stock.