Linux Preloaded offers a list of computer shops, that ship with Linux preinstalled.
System76, based in the USA, sells computers with their own operating system called Pop!_OS. You can also choose Ubuntu LTS (Long Term Support) at the checkout.
ZaReason, based in the US, offers hardware with a variety of Linux operating systems to choose from. They ship to the US and Canada.
Tuxedo, based in Germany, sells individually built computers in many sizes. The hardware ships with Ubuntu, openSUSE or their custom TUXEDO_OS operating system.
Entroware, based in the UK, ships Ubuntu Laptops to Europe.
The Linux Laptop Company
The Linux Laptop, based in the USA, sells name brand laptops (such as Dell, Asus, Acer etc). On the software side, you can choose from Ubuntu, Linux Mint and Fedora.