To save space in my books, I sometimes refer to online resources. These are the resources regarding the trip from Harmony to Fayette during which David Whitmer, Joseph Smith, and Oliver Cowdery met the divine messenger who was taking the abridged plates to Cumorah.
Here's an overview.
In May 1829, Joseph Smith, Jr., and Oliver Cowdery were translating the plates at Joseph's home in Harmony, PA.
In the morning he went to the field and found that he had 2 heavy days work before him He then asked the lord to enable him to do this work sooner than the same work had ever been done on the farm before and he would receive it as an evidence that it was the will of God for him to engage in forwarding the work which was begun by Joseph Smith. he then fastened his horses to the harrow and drove round the whole field he continued on till noon driving all the way round at every circuit but when it came to be time to eat dinner he discovered to his surprize that he had harrowed in full half the wheat. after dinner he again went on as before and by evening he finnished the whole 2 days work
Lucy Mack Smith (1845) explains that Joseph was told through the Urim and Thummim to contact David Whitmer. Joseph gave the abridged plates to a divine messenger before leaving Harmony.
*You can find this account in these references, although apparently not transcribed exactly: "Edward Stevenson Interview (1) 22-23 December 1877, Richmond, Missouri Diary of Edward Stevenson," LDS Church Archives, Lyndon W. Cook, ed., David Whitmer Interviews, 1993, p. 13; also Dan Vogel, ed., Early Mormon Documents, 2003, vol. v, p. 30.