Laptops come with a self-regulating power supply brick so voltage isn't an issue.

However, Doha isn't the best place in the world to buy PCs and their peripheries/accessories in terms of variety and price. The issue is that if you buy the computer in Canada what do you do if you need support/warranty. If it's international then there are dealers here for Sony, Dell, Lenovo/IBM and some others.

Cellphones you can buy here no problem. As a matter of fact some phone manufacturers release their phones in the Gulf market before anywhere else in the world.