I'm flying to Tokyo with my GF for three weeks. We haven't sorted an itinerary yet.
We are both 25. Shopping, entertainment, food, alcohol.
We also would like to do some sight-seeing..
Not just within Tokyo! Happy to travel around.
Alcohol is cheap compared to the prices in Australia, so drink your hearts out. You especially have to dive into Japanese whiskey if you're into whiskey, because that stuff is meeeeega expensive outside of Japan.
Food is relatively cheap as well, but barbecue places will usually run you about $30-50 per person.
If you just need a list of places to go around/nearish Tokyo, check out;
Akihabara - Lots of electronics and anime/manga goodies if you're into that kind of thing
Asakusa - Very 'traditional' Japanese place with a biig temple to see
Harajuku - Umm, quite a trendy place for youngsters, lots of clothes shops and such, there are also temples/shrines near by
Shinjuku - Shopping and close to nightlife/red-light district at kabukicho
Shibuya - Shopping
Ikebukuro - More shopping, kind of like Akihabara
Odaiba - Toyota car show and some more shops, a very modern place
Roppongi - Nightlife/red-light district
Ginza - Heaps of boutique stores, and don't forget to visit the Tsukiji Fish Market close by, you have to try sushi there
Well, I've probably missed a lot of stuff, but those were some of the places I visited and revisited during my two week stay in Tokyo a while back.
Since you have three weeks, you should be able to travel outside Tokyo if you somehow run out of things to do! I think you should visit Osaka as well, it's only a ~3 hour train ride away.
Hmm, I didn't look out for any dedicated A/V stores in particular, so I can't really help.
There's a place called Yodobashi Camera, they have large stores in Akihabara and Shinjuku, it's kind of like a massive JB HiFi/Harvey Norman, and they've got plenty of headphones on display at both locations. Since I stayed in Shinjuku, I spent a lot of time visiting the store there, they're open until quite late too.
What I loved about the stores was that you can just help yourself to the gear on display, you don't need to bother a shop assistant to set anything up, it's all just sitting there ready to go. This also applied to the cameras, it made it so much easier testing out all the cameras to see which one was right for me.
I am doing my internship in Tokyo right now. If you like fashion do yourself a favor and get off at Harajuku and walk towards Omotesando (15 min walk), the whole place is filled with fashion from around the world. You can also walk from Shibuya to Omotesando (which i recommend, you see more if you walk instead of taking the train everywhere). But heads up, unless you are supppppper rich, you are going to feel soo poor lol, its one of those areas where you feel like all the money in the world won't be enough (same goes for Ginza area). Also I highly recommend visiting Asakusa really early in the morning, and then around 1-2 pm start walking toward the SkyTree (tallest tower in Japan), you don't need direction just look up and follow the tower. Once you are there check out the stores and maybe even the aquarium (its okay, not as big or cool as the one in Osaka). Buy a skytree lift pass for 4:30-5pm. So when you get up you see the city, and then just wait an hour or so and you get to see the beautiful skyline.
For Audio there's tons of store in Akihabara that sells Audiophile gear, the most common place is yodobashi Camera or Bic Camera. They both carry a wide range, the best part as Deadlylover pointed out is that you can sample most of the sub 1000$ headphones in the store without having to ask the workers there (you can try most of the expensive as well, you just have to politely ask). I was there recently and I tried the HD800 and Se846 (they have a lot other high end brands like Ultraones, AKG, Hifiman, Beyerdynamic, Grado, Denon, Audio-tech, fostex, Audeze and a lot more).
For going out, if you want to party with the locals, go to Shibuya. If you want to party with expats, exchange students, and other foreigners go to Roppongi. Some clubs I would recommend are Ageha (biggest in Japan four main sections with different music), Womb (awesome sound system, 3 floors, mostly electronic music), Vision ( 3 music sections, hosts a lot of edm shows), and Feria (super fancy, 5 floors, strict dress code). But theres enough bars and clubs in Tokyo, that you can go to a different one everyday without going to the same one twice, so go on an adventure. Most clubs don't close till 5-6 am, then some people go to after parties that goes until the afternoon lol, the city that never sleeps. Drinking on the street is legal, and you can buy drinks at convenient stores (literally one or two on every block), so pre-drink hard before lining up for a club (or drink in line).
Whatever you are into, there's tons of stuff to do here, so enjoy!
The previous suggestions are all good...but this is my favorite place in Tokyo.
Go and have lunch in the museum cafe. It's a trip...
Also if you go to Osaka, which you should, you must also visit Kyoto.
While in Tokyo, day trips to Hakone, Kamakura and Yokohama are worthwhile.
Depending on your tickets, if you can fly into Tokyo and home from Osaka yo can build a nice itinerary.
Edo Wonderland - my friend keeps on raving about it and promised that if I ever visit him in Japan while he still works there, he'll rent me the Samurai armour. When you go in, part of your ticket price goes to the costume, and the full-body armour is the most expensive to rent. I'm planning on going next year, but when I do rent that black armour, I'm not taking the kabuto though - I'll wrap my head like the Dragon of Echigo. Also if you can catch local theater, see if the Noh of Atsumori is being performed anywhere in the area. Also the Noh of "Sisa," an exerpt from Jose Rizal's 19th C novels, for which a new Noh was written and initially performed by a Philippine Noh company (someone told me there might be performances of it in Indonesia also) and I think it's occasionally performed by Japanese students. I wanted to do the costume redesign and make a hybrid of the kimono and our own suits and dresses from the period, but Noh is highly traditional despite the new material (also my friends thought doing costume design was "ultra gay," unless it's the idiotic female superhero costumes/MMORPG "armor"). Snacks and tea are served at the intermission, and they're usually by good chefs, so that also figures in the ticket prices. Also, dress up as this is more like Opera than Broadway or West End, so it might be better to watch Noh in Edo Wonderland if they have any performances there since you're already paying for a costume (you might not get into the show if you pick the cheaper costumes, given the whole point of the amusement park is to recreate the era barring getting hurt or killed).
As others have said, Yodobashi Camera and Bic Camera have headphones, but I think you may be thinking of e-earphone, it's a store dedicated to audiophilia, also in Akihabara. You can listen to all the used stuff in glass cases too, including amps, dacs, cables. If you want serious listening, I'd recommend going on weekdays as it can fill up.(Not the best for open headphones)
The Audiophile cans were playing this and the T1 were kicking the tail off everything else.
Enjoy. If you go to e-earphone they do not let you listen to everything anymore unless you are really looking to buy and taking pictures is frowned upon heavily unless your a rep. They got price tags and stuff. They expect everybody knows that it's a business.
If you wanna make connections keep your camera in pocket in that place and take the pics at EDION. They don't like it too but they are a monster chain.....they'll get over it
(EDIT: I took the pics out because I cannot post them in multiple threads. You are gonna see them all soon anyway(