Building a laptop

I don't think it'd be hard, it looks easy(compared to a desktop) although I haven't done one.

First you buy a notebook kit,
http://www.directron.com/laptopbarebone.html
then you pick a cpu, hard drive, optical, ram, OS, etc, and put it together.

It'd be expensive though, as a kit is like $600-800 usd, not counting everything else.
 
I would not suggest you do so. All laptops/notebooks require special tools for assembly, because they are very small and there's very limited space for you to work with. I've been in the laptops/notebooks industry for 4 1/2 years I've seen many customers destroyed the CPU's or mobos or altogether. Besides that, the price is also very high comparing to the comparably equipped desktop PC.
 
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