The Diary and Letters of Lt William Rhandamanthus Montgomery of Co F 3rd Ga Sharpshooters have been published in a book titled Georgia Sharpshooter (Mercer Univ Press, Macon, Ga , 1997) and provide some good information on this unit. Gerald Smith's book "One of the Most Daring of Men" the biography of Gen Wm T Wofford also provides some info on this unit.
The compiled service records of men serving with this unit are available on microfilm at the Ga State Archives and NARA.