How detailed do you want them? New Apartment buildings that are trying to sell apartments usually have the floor plans on their websites.
I guess to find ones do a Google like 'new apartment developments in xxxxxxx' then look for some site names and then Google the site names and maybe find a new building getting built
For houses it's more difficult, there are building companies that have housing plans but normally only if you are looking to buy can you see them to prevent competitors getting their designs.
You can search resort villa floorplans. They like to show off their plans and all over the world there are constantly new resorts being built.