Like Ishimaru, LAOX is a large duty-free electronics department. LAOX has large home theatre, TV, and cell phone departments, frequented by American tourists. The place isn't especially remarkable though, especially since next door Ishimaru has far more selection. Sure, it's duty-free, but are you really going to ship that flatscreen back from Japan?
Ishimaru is an immense shopping complex comprised of three or four high-rises clustered around one of Akihabara's busiest intersections. You've probably walked by several times if you've used the train station. Two buildings carry music, one carries touristy souvenirs, and the last is an electronic department store of sorts, carrying everything from videogames to air conditioners to home theatre.
One of the music buildings is devoted exclusively to Jazz and Classical, boasting 6 stories plus a listening room. The selection, as you can imagine, is mouth-watering. Lots of special editions, obscure artists, and employee-assembled collections by theme and artist. Unfortunately, everything is alphabetized in Japanese, making it very difficult to locate things if you don't know the language. A real shame. The pop music building, which also houses DVDs (live action, anime, adult) is organized similarly. Also, all DVDs are encoded in the Japanese region, so you can't play them on U.S. hardware. The selection, again, is incredible though, and every aisle is packed with screens showing previous or special promotions.
I don't recommend going to Ishimaru's souvenir building. The souvenirs are poor quality - 4,000yen nightgowns advertised as kimono's for foreign tourists who don't know any better. Go to Oriental Bazaar instead - even the Japanese tourists shop there.
The electronic department store is fun to browse in. However, people don't speak English very well and I saw most Americans (it's mostly tourists) looking and not buying.
A lot of the electronics are duty-free, although the music isn't. Passport required.