Spurred on in part by Edmond Halley's appeal, nations sent expeditions around the globe in the 18th century to time the transit.  Here are some outside links:

http://www.transitofvenus.nl/history.html
Thorough list of historical observations of the transit of Venus.  An overview of places where the transit of Venus has been observed in the past and which  could be identified using Google Earth. The stations are listed by sponsoring country and nationality, following the longitudinal position from west to east. Many entries have links to primary sources; from Steven van Roode.

http://transitofvenus.nl/wp/past-transits/bibliography-1761-1769/
Extensive bibliography for all things related to the 1761 and 1769 transits of Venus; from Robert van Gent.

http://www.astronomy.ohio-state.edu/~pogge/Ast161/Unit4/venussun.html
Humorous introduction to the characters who set out to time the transit of Venus in a collective international effort to quantify the size of the solar system.  From Richard Pogge.

http://youtu.be/41f2gN0decg
UNESCO -17- Science and Illustration: The Transit of Venus is a high-quality production that chronicles the challenging 18th century expeditions of Chappe, Hell, Cook and others.  Video conveys the confluence of factors in the Age of Enlightenment that propelled the global quest to determine the size of the solar system; 46 minutes.

Out of Old Books (Le Gentil and the Transit of Venus), by Helen Sawyer Hogg; scanned from Journal of the Royal Astronomical Society of Canada, 1951, and provided by NASA Astrophysics Data System (ADS). This four-part series of articles chronicles Le Gentil's thwarted efforts as well as his triumphs, with English translations excerpted from Le Gentil's memoirs:

• 2/1951 Expedition beginnings to frustrating 1761 sighting at sea; years in Manila;
• 4/1951 Departure from testy Manila; two experiences at sea, including the arguing pilot and sulking captain;
• 6/1951 Le Gentil recounts the cloudy morning of the thwarted 1769 transit; nearly shipwrecked trying to sail home;
• 8/1951 Trip home, looted estate, eventual retirement.

Another version of Out of Old Books (Le Gentil and the Transit of Venus), by Helen Sawyer Hogg, appears at http://cseligman.com/text/atlas/LeGentil.pdf


http://www.amazon.com/Voyage-dans-mers-lInde-loccasion/dp/0543935973
Le Gentil's autobiography (in French) is available for purchase.

http://www.oneminuteastronomer.com/2010/10/05/le-gentil/
One-Minute Astronomer story What Doesn't Kill You Makes You Stronger features the "epic hardship and bad luck" of astronomer Le Gentil and his travails. 

http://science.nasa.gov/science-news/science-at-nasa/2004/28may_cook/
James Cook and the transit of Venus, from NASA Science News

http://coombs.anu.edu.au/~cookproj/archive/royal_society/green.html
Astronomical Observations...by Mr. Charles Green, formerly Assistant of the Royal Observatory at Greenwich, and Lieut. James Cook, of His Majesty's Ship the Endeavour.  Excerpt from the Endeavour Project archives.

http://www.jcu.edu.au/aff/history/southseas/
South Seas Project

• http://www.jcu.edu.au/aff/history/southseas/journals/index.html
  Endeavour journals and map index.
• http://www.jcu.edu.au/aff/history/southseas/journals/maps/17690628.html
  Endeavour journals and interactive map.
• http://www.jcu.edu.au/aff/history/southseas/journals/maps/contents.html
  Interactive maps of the Endeavour voyages.
• http://www.jcu.edu.au/aff/history/southseas/journals/maps/17690628.html
  Map of Cook's Circuit of Tahiti, Windward Is., 26 June-1July, 1769.
• http://www.jcu.edu.au/aff/history/southseas/biogs/P000085b.htm
  Brief summary of the role of transits in determining the Astronomical Unit.
• http://www.jcu.edu.au/aff/history/southseas/journals/Parkinson/045.html
  Sydney Parkinson's data for the transit, recorded in his journal.

http://www.melbourneobservatory.com
Transit of Venus site emphasizing the 18th and 19th century transits.  Two of Janssen's photo-heliographic devices are apparently in Australia--one in Melbourne and one in Sydney; from the Melbourne Observatory.

http://www.arm.ac.uk/history/richobs.html
Image of Richmond Observatory, "built by George III, specifically to observe the Transit of Venus in 1769;"  from the Armagh Observatory.

http://explorepahistory.com/displayimage.php?imgId=2871
Map of transit of Venus by David Rittenhouse.

http://www.archive.org/details/astronomyexplain00fergrich
Book:  Astronomy explained upon Sir Isaac Newton's Principles : and made easy to those who have not studied mathematics : to which are added, a plain method of finding the distances of all the planets from the sun, by the transit of Venus over the sun's disc, in the year 1761 : an account of Mr. Horrox's observation of the transit of Venus in the year 1639 : and, of the distances of all the planets from the sun, as deduced from observations of the transit in the year 1761.