Easily, I've made many upgrades to existing PCs, dismantled a number including the occaisonal laptop, and have experience in modifying hardware with overclocking to achieved the highest reliability and performance ratio.
However, due to have always been a student, having no employment and only ever buying laptops as my primary PCs now, I haven't ever built from scratch (unless you count stripping a PC and putting it back together). I do frequently build them theoretically though (every month or so) using the best sources I know to see how the market is going cost to performance wise across the spectrum (from the unlimited budget PCs to mid range gaming rigs, to under £300 and see if I can still get it considered gaming worthy).
I'm in the process of salvaging my last laptop for parts and to see if I can identify the problem myself, run some tests on bits of the hardware and such. Was hoping to salvage the screen but it turned out the cost and time involved in the effort was more than buying a new LCD monitor.