Here in the "good" ole US-of-A, computer stores vary. There are the local shops that sell everything for either jacked-up prices or very good prices. They tend to be fairly small, having close aisles and boxes of goods stacked up here and there.
The bigger chain stores vary just as much as the smaller stores. Staples doesn't have much variety of computer products. They specialize in office equipment more than anything. That is, they sell desks, chairs, printers, pens and pencils, paper shredders, and some computer hardware. The stores themselves are quite big (relatively speaking). Fry's Electronics here on the West coast are warehouse-sized places that sells everything electronic from R/C cars to graphics cards to appliances to car stereos, and lots of things non-electronic from magazines to soda (they once had 6-packs of Coke for $0.99!). The ceiling at Fry's is about five-stories above your head, and it takes quite a few minutes to walk from one side of the store to the other. Some even have themes, like the one in San Jose, which has an Incan/Indiana Jones theme. I've been to another one which has a futuristic theme.
Taiwan is quite small in size in comparison to the US, so things are understandably more compact. But, as stereotypes suggest, Americans like things big, and I guess our computer stores generally prove that right.