Basically, Japanese addresses work by narrowing down from larger to smaller.
Japanese cities are divided into ku, which are roughly similar to the boroughs of New York City in that they have their own city halls.
The ku are divided into cho, many of which were once independent villages, as old maps of Edo show. In modern Japan, these are roughly equivalent to large neighborhoods.
The cho are divided into chome which are numbered subdivisions of the cho.
The chome are divided into numbered banchi, which for all practical purposes are city blocks.
Finally, the banchi are divided into shikichi, or lots.
I'll illustrate with my address when I lived in Japan:
Nakano-ku
Nogata 2-1-5
The address tells you that I was in Nakano-ku, which is the first major stop after Shinjuku on the Chuo line, the main JR line running west of the city.
My cho was Nogata, but whenever people in Nakano asked where I lived, I said "Nogata ni-chome," or "second chome of Nogata."
The address also tells you that I lived on the first block in Nogata 2-chome and on the fifth lot to have a house built on it.
So how do you find anything in Japanese cities, especially since most streets are unnamed?
You use maps and learn to ask directions. When you're in Japan, you'll see that newspaper and magazine ads, even in the English-language press, contain little inset maps, showing how to reach the business from the nearest transit stop.
Kodansha's Tokyo City Atlas somehow manages to put all those names and numbers on its maps--and in two languages. It has larger maps of all the tourist areas, and browsing through it will give you an idea of how the city is organized.
When I invited people over, I told them my address, but my actual instructions ran like this: "Walk out the north entrance of Nakano Station, go through the Sun Mall and Broadway Mall (two continuous shopping arcades), turn left, cross the street, turn left again by the doctor's office that has a palm tree in front..."
If you're not sure where your hotel is, look up its website. There's bound to be a map showing the location.
In any case, don't worry about getting lost. Japanese people get lost all the time. It's part of the adventure.