Two brothers, painted panel, Fayum, Egypt. 2nd c. C.E., Cairo, Egyptian Museum. See Anne E Haeckel, "Brothers or Lovers? A New Reading of the "Tondo of the Two Brothers" Bulletin of the American Society of Papyrologists for more information. (Image Source: Wikimedia Commons, Public domain)
Collections of primary texts in anthologies can be good for browsing. They touch on many different issues, often excerpting brief passages from full works that you can find in the tricolleges or through interlibrary loan.
The primary source collections below relate to issues of race and ethnicity in Antiquity.