There's a really interesting book series called "The Cross Time Engineer". It puts a modern day engineer back into the middle ages and follows his path to rebooting an industrial society from just the knowledge in his skull.
While it's surely not wholly accurate, everything related to the material science and technology level is at least plausible.
And for a cynical take on the "modern engineer brings advances to middle age" also taking into account social aspects, Mark Twain's "A Connecticut Yankee in King Arthur's Court" (http://www.gutenberg.org/ebooks/86) is good reading.
Don't forget "The man who came early", which deals with just the sort of cannot-reconstruct-the-technology-chain issue in case of accidental time travel.
I think Orson Scott Card also writes something similar in the book 'Hot Sleep'. Long story short, some people wanted to recreate society by starting a primitive colony where there was know to be iron ore under the surface. They didn't fare too well...
While it's surely not wholly accurate, everything related to the material science and technology level is at least plausible.
http://www.amazon.com/Cross-Time-Engineer-Adventures-Conrad-...