http://www.archive.org/stream/descriptivelisto00smit#page/n7/mode/2up
Descriptive list of antiquities near Loch Etive, Argyllshire(1872) BY Smith, Robert Angus, 1817-1884; Society of Antiquaries of Scotland

http://www.archive.org/stream/accountofexcavat00bryc#page/n7/mode/2up
Account of excavations within the stone circles of Arran (1863) by Bryce, James, F.G.S; Society of Antiquaries of Scotland

http://www.archive.org/stream/chipsfromoldsto00maclgoog#page/n6/mode/2up
Chips from old stones, by the author of 'Hill forts and stone circles of ancient Scotland'. (1881) by Christian Maclagan

http://www.archive.org/stream/ancientpillarsto00moor#page/n13/mode/2up
Ancient pillar stones of Scotland; their significance and bearing on ethnology (1865) by Moore, George, M.D

Or have a delve into some old free books while you're waiting... not up to date but quaint with the odd hidden gem.