Start with the County Register. Many have old building permits and even plans on file. You may have to do a lot of hands on research, once you determine from your county authorities the right place to look, as many of the older records, as is the case in my area, have not been digitized.
My favorite research items on older homes are to consult the City Directory (usually published by a title company for business reference) at the public library. Just start with the year the house was built to find out who lived there, their profession, etc. and work your way forward. You can usually put together a pretty interesting story of what happened with the house and maybe contact some of the families if they are still in the area. My public library keeps a vast photo library which contains a lot of neighborhood and individual house photos, and you can also go through old newspaper ads.