Well, the desk in original top post is custom made. Reasons I think so are:
3 legs, none of them near the wall.
So the desk itself is likely attached to wall with separate L shaped mounts and the legs are there just to support weight, not to keep it from moving.
so.. your best bet is.. go get a slab of wood, go buy legs/mounts, build your desk.
Or go Ikea route:
http://www.ikea.com/gb/en/catalog/products/S49004756/
That is still relatively small though, at 150cm
If color is not an issue, you could try it bigger, at 200cm. too bad it isn't as wide anymore (60cm instead of 75, less space for keyboard/mouse)
http://www.ikea.com/gb/en/catalog/products/S69929643/
edit: Actually, relooking at it, it is likely black variant of the second...