It surprised me to see that many of the british data sources are of the "visit the official archive or buy digital access" kind. Also, judging from a few samples at http://www.naval-military-press.com/cd-rom/, most of it is Windows only, and not priced for impulse buyers (for example 220 pounds for a database of all British who died)
Also, you could visit it !
Like the famous untouched apartment in Paris. Never really understood what it became except they sold painting they found in it.
http://www.telegraph.co.uk/news/worldnews/europe/france/8042...
I visited the Getty Museum this summer and found the displayed rooms of European apartments quite great and interesting, as I was fascinated by the Napoleon III ones at the Louvre.
In Oslo there's a museum called Norsk Folkemuseum [1] (Norwegian Museum of Cultural History) that includes 160 buildings that were dismantled and moved - some of them from other parts of the country.
Ranging from a stave church built ca. 1212 [2] that was moved to the present location in the 1880's, to a collection of five buildings built in the 1800's in an old part of Oslo that were moved to the museum when that part of Oslo was re-developed in the 1960's.