So how do you give directions? I know you must have a system, but I'm not sure exactly how it works. "Head down to Block 16, take a left and turn right at block 22"?
"Turn right at the next crossing, then at the 4th street turn left, then after you see the Buddhist temple turn right". Major streets also have a name, and there are maps at a lot of places, most importantly at the train station. Around my place there are even detailed, apparently hand-drawn maps with the shops' names written on them.
In the block themselves there may also be a map of the block with the houses and the family names of the owners. Houses themselves don't have a number plaque but they have the owner's name at the entrance. Apartment buildings tend to have a (more or less pompous) name as well. Here "mansion" means an apartment :)
Generally you don't need to ask though, since the websites for japanese shops usually have a detailed map, and people who invite you will give you landmarks.
In the block themselves there may also be a map of the block with the houses and the family names of the owners. Houses themselves don't have a number plaque but they have the owner's name at the entrance. Apartment buildings tend to have a (more or less pompous) name as well. Here "mansion" means an apartment :)
Generally you don't need to ask though, since the websites for japanese shops usually have a detailed map, and people who invite you will give you landmarks.