Style = Term used for a coherence of qualities in periods or people.
Grove Art Online gives the above succinct definition and then goes on to qualify it by saying that "style" is one of the most difficult concepts in the lexicon of art and one of the most debated. "Each of the component terms of style has been disputed, and style itself has been rejected on various grounds...."
Although the term "style" is problematic, there are many books written and websites created to assist researchers in learning what architecture and interiors created in a certain time/place tended to look like.
For those researchers (students of material culture and architecture, theater set designers, fiction writers seeking ambiance, DIY house restorers) who have requested a bibliography and guide, I compiled a list of resources predominantly available for browsing at the Kohler Art Library, UW-Madison. Note that Steenbock Library and other campus libraries are also fruitful sources for books on interiors and design.
Contact the Kohler Art Library if you have suggestions for improving this guide.