通販 (short for 通信販売) means mail order. For those unfamiliar with this term, it refers to the purchasing of products by mail delivery via telephone or websites. I wasn’t that much a fan of buying things online before I came to Japan simply because you don’t get to see the actual product but I’ve come to see its benefits especially when you can save a few thousand yen by purchasing online even with the shipping costs. Some of the companies even offer free delivery nation-wide.
Most of the time, if possible, I would go take a look at or even try out the actual product at nearby stores and then purchase them online. If I can’t find the items at local stores, it really depends on what the item is. I may rely on online reviews or simply give up the idea altogether.
For books, I usually get used items off Amazon Japan or Bookoff. If on the site, it says the book’s condition is as good as new, it will arrive as good as new. I’m serious! That is why it doesn’t make much sense for me to purchase new items unless I’m really eager to read a new release.
For everything else including computers, furniture, TV, electronic dictionary and what not, I usually get them off 楽天 (Rakuten) or 価格.com (Kakaku.com). I have my reserves regarding used electronics.
But again, before you start buying multiple items via mail order, you should find out which is more worth it depending on the item you are buying. Mega shops such as ビックカメラ (Bic Camera) and ヨドバシカメラ (Yodobashi Camera) offer free membership and with each purchase, you get 10% of the amount paid credited into your membership card. This means, if you spend ¥10,000, you get ¥1,000 credited into your membership card which can be used for your next purchase. You can also choose to store the credits and use it whenever you like.
This would also mean that if I were to buy an iPad2, I’d most likely get it from Bic Camera or Yodobashi Camera as opposed to an Apple store even though the Apple store offers a free iPad2 case because at approximately ¥52,000 for the 32GB version, I’d get ¥5,200 credit which I could use for something else including a case which would set me back about ¥3,000 only.
There’s no single way for everyone so do your homework and see what suits your needs best.