A guidebook for new researchers in Classics is the Handbook for Classical Research which is both useful and entertaining (and I mention that because these sorts of guides tend to be worthy but dull).
It includes: The Basics, Language, The Traditional Fields, The Physical Remains, The Written Word, The Classics and Related Disciplines, The Classics since Antiquity.
David Schaps, Handbook for Classical Research, London: Routledge, 2011.
Available from the Library