It's not free as in speech, only as in beer, but d100d.ru is a complete set of plans for building a house. It was specifically designed so that people who can't afford an architect can have a complete set of documents and architectural decisions to build a house on their own or hire a contractor without compromising on quality, as they can't afford to fix errors either.

Unfortunately, it's practically unusable in the US, as the ground floor is built from AAC, very popular in Russia and practically unheard of in the US. It's probably too small for American tastes, too.