How About Some Examples?
Here are some books and series that fit the genre really well, even if they weren’t all written with “dreampunk” in mind. I’ve tried to select works that deal in some way with the internal/
The Alice stories (1865–1872) by Lewis Carroll
The Dreaming Jewels (1950) by Theodore Sturgeon
Solaris (1961) by Stanisław Lem
The Three Stigmata of Palmer Eldritch (1965) by Philip K. Dick
The Dream Master (1966) by Roger Zelazny
Ubik (1969) by Philip K. Dick
The Chronicles of Amber (1970–1991) by Roger Zelazny
The Lathe of Heaven (1971) by Ursula K. Le Guin
Up the Walls of the World (1978) by James Tiptree Jr.
White Light (1980) by Rudy Rucker
The Dark Tower series (1982–2004) by Stephen King
Hard-Boiled Wonderland and the End of the World (1985) by Haruki Murakami
The Sandman series (1989–1996) by Neil Gaiman
Snow Crash (1992) by Neal Stephenson
The Vurt series (1993–1997) by Jeff Noon
The Newford series (1993–2004) by Charles de Lint
Fight Club (1996) by Chuck Palahniuk
Neverwhere (1996) by Neil Gaiman
Perdido Street Station (2000) by China Miéville
The Kefahuchi Tract trilogy (2002–2012) by M. John Harrison
The Circle series (2003–2009) by Ted Dekker
The Scott Pilgrim series (2004–2010) by Bryan Lee O'Malley
A Monster Calls (2011) by Patrick Ness
The Darkening of the Light (2012) by Tessa B. Dick
The Diviners series (2012–2020) by Libba Bray
Hoodoo (2016) by Ronald L. Smith
Letters to the Black Underground (2016) by Yelena Calavera
Jerusalem (2016) by Alan Moore
Storm Dreams (2016) by Jeb R. Sherrill
The Roam series (2016–2017) by Dez Schwartz
The Strange the Dreamer series (2017–2018) by Laini Taylor
The Soul Sleep Cycle (2017–2019) by David Michael Williams
Urban Gothic (2019) by Stephen Coghlan
I’m a Gay Wizard (2019) by V. S. Santoni
Next: Dreampunk in Film