I found these almost by accident in my travels through the internet. As I was trying to learn more about clocks and clockmaking I found a few books digitzed by google that are now in the public domain, so I thought I would share. The gear book was the most helpful to me. I hope these can help someone else as well.
The biggest help with drawing gears was this one: American machinist gear book By Charles Hays Logue, Reginald Trautschold (1922)
The next one has a chapter (chapter 10) on gear trains: Elements of mechanism By Peter Schwamb, Allyne Litchfield Merrill (1904)
And the last one I found is self explanitory: Watch and clock making By David Glasgow (1885)
Great Book: Jules & Hermann Grossman, Lessons in Horology, The Keystone, Philadelphia, 1905, pp. 171-189
A good source for general information, including maintaining power, is the book „A Rudimentary Treatise on Clocks, Watches and Bells“, by Edmund Beckett. An online version can be found at http://www.nawcc-index.net/Articles/17576.pdf
Harrison’s Chordial Pitch Gearing – Part 1: http://www.livingstonstandardtime.com/misc/Part%201.PDF
Harrison’s Chordial Pitch Gearing – Part 2: http://www.livingstonstandardtime.com/misc/Part%202.PDF