Originally posted by nzguzzi:

I'm after something cool like a long house I can just collect mats, click the button and boom, done and dusted.

There are circular tower ruins that have a basement area. In the swamps, these are unusable due to being flooded.
However, there are some that you can find in the mountain biome that are intact and usable. All they require is building a ground floor above and secure that with a wall, door and roofed chimney. This makes an excellent place to rest up overnight while you mine out all the silver you will need during the day.

If it is a longhouse you're after, then look for meadow areas beside the shore that are close to the swamp biome. There, you can sometimes find whole 'abandoned' villages that have many buildings, including a fine longhouse.
All you have to do to is reclaim them is to clear the Draugrs out and destroy their nests inside the buildings. You may then build workbenches to claim the buildings and then it's a simple matter to make any repairs... it isn't just a case of clicking a button once, but repairs don't take long and it is an easy way to acquire an outpost without having to build one yourself ;)