Physically browse: Find the call number range HQ 76.3 on the ground floor of the Main Library, and peruse the shelves, keeping an eye out for older books.
Search the catalog: Use the tips suggested for Secondary Sources, but add a date limit that corresponds with your research period.
Christopher Street (NYC; 1976-1995) VCL has 1987-1995 in print in the Periodical Room (call number HQ 75.C48)
Gay Community News (Boston; MA, 1973-1999) VCL has 1973-1996 (Microfilm 699); Articles also available online via Alt-Press Watch and Gender Watch, but it's incomplete access. Try the microfilm- you might like it!
Bay Area Reporter (San Francisco;, CA, 1971- ) Archival database of obituaries
Dallas Voice (Dallas, TX, 1984 - present) One of the collections in the University of North Texas Digital Library
The Empty Closet (Rochester, NY, 1971-present) Keyword searchable database of the newspaper, hosted by the University of Rochester
Focus Point (Minneapolis, MN, 1994-2000) Part of the Minnesota Reflections project, hosted by the Minnesota Digital Library
GLC Voice (Minneapolis, MN, 1979-1992) Part of the Minnesota Reflections project, hosted by the Minnesota Digital Library
Southern Voice (Atlanta, GA,, 1988-1995) One of the newspaper collections in the Digital Library of Georgia
Washington Blade (Washington, D.C.; 1969-1982) Keyword searchable database of the newspaper, hosted by the DC Public Library
In the Life (PBS; 1992-2012) Archive of the PBS television news series, hosted by the UCLA Film and Television Archive
Before Stonewall: The Making of a Gay and Lesbian Community (Vassar DVD collection) Seminal documentary from 1985
Sexual inversion, invert
Pederasty (between two adults)
Hermaphroditism, psychical hermaphroditism, pseudo-hermaphroditism
Gyandry, gyandrism, gyandroid
Eviration / defemination
For 20th century lesbian fiction, see the contemporary novels by Jane Rule, Claire Morgan (aka Patricia Highsmith), Ann Aldrich, Ann Bannon; Femmes Fatales series of lesbian pulp novels re-published by the Feminist Press.