One of these days I'm going to make a classical guitar and if I do it may well be one of these, a Panormo guitar. Louis Panormo was a guitar maker active in London in the 1840s and 50s. His instruments are actually based on earlier Spanish designs.
St Cecilia's Hall, an 18th century concert hall in Edinburgh's Old Town (in the Cowgate, just off Niddry Street). We went to a guitar concert there during the 2011 Edinburgh Festival and were amazed to see all these early guitars on display in the area that they served coffee in at the interval. They were in glass cabinets, mind you.
Actually, I've no idea how to make one but did come across a luthier (a maker of stringed instrument, especially guitars) called Gary Demos who had made one and shows how on his website. Another interesting website that discusses many 19th century guitars can be found here.