Tell us about your past of building desktops. What you need to know is that laptops are very different. No standards as to motherboard factors and more.
Tell us why you want to build your own laptop.
As to parts, parts are all over the place. Just one thing. They don't fit together like desktops do.
I am trying to build a laptop but I hear it pretty hard to find good laptop parts so anyone with anything that can help it would be appreciated. Websites with parts or store locations all welcomed thanks...