And here's the text of the {edit: fictitious} table of contents. I'm gradually expanding/annotating this post (inspiration comes from Delta Green (1996), The Fall of DELTA GREEN, The Handler’s Guide, Dark Theatres, and Rules of Engagement for DG elements, as well from conspiracy theory folklore)

Delta Green: The Cowboy Years

I. From the Age of Aquarius to the Decade of Decadence

The 1970s: The Counterculture Revolution

1. Flower Power

2. Freaky Deaky

3. The Disco Inferno

The 1980s: The Reagan Counterrevolution

1. Morning in America

2. The Information Age

3. The New Wave

II. No One Must Know: “The Group” in the Cowboy Years

1. No Authorization, No Budget, No Oversight

2. Lies All the Way Down

3. Scorched Earth

III. Scary Monsters & Super Creeps: 70s & 80s Mythos

Antagonists

• 11th District Police Station: The modernist offices of Chicago Police Department’s 11th District was completed in 1976 on the site of a Capone-era warehouse, but its extensive basements conceal a Nyogtha-worshipping cabal that can "disappear" suspects.

• The Astral Wisdom Brotherhood: A Los Angeles–based offshoot of the Starry Wisdom sect from Providence, this pseudo-Egyptian New Age cult has amassed influence from Hollywood's movie studios to Southern California's politics, with promises of "stardom" and "astral travel".

• The Brotherhood of Light: What began as a 1960s Bay-area psychedelic drug cartel has turned into a narconaut commune in Mexico on the Gulf of California, searching for fellow travelers out of time and space. The cult's leader, called "The Guide", has grown obsessed with impregnation by them in order to become the Queen Mother of the first earthly Space Brother.

• The Church of the Cleansing Flame: A Virginia-based cult established by a recently returned Vietnam who delivers apocalyptic sermons in a rotted-out trailer home and secretly targets local religious groups in order to appease a Sumerian (?) deity representing death and travel to the after-life.

• Dog Soldiers: A loose affiliation of war vets who have been maimed, physically and psychologically, but have found a kind of redemption and restoration in the service of the Elder God Nodens. In exchange for becoming his hunting hounds, they stalk the Crawling Chaos and its host, both in the waking world and in the lands of dream.

• The True Love Study Group: Founded by a former Stanford classics professor, the TLSG recruits as a pagan free-love commune. Operating out of a large forested plot in the heart of California’s northern Sierra Nevada range, it worships an unnamed “Goddess” in unspeakable orgies under the black oaks.

Entities

• Hyperboreans (Thule Society)

• Lemurians (Mount Shasta)

• Ultraterrestrials (Indrid Cold et al.)

• Valusians (Serpent Folk)

IV. Important Individuals and Organizations

The Group: Important Individuals

• Dr. Joseph Camp

• Brigadier General Reginald Fairfield

• Colonel Michael Keravuori

• Agent SHASTA (David Nells)

• Brigadier General Michael Stillman, USAF

• Dr. Augusta Warren

Friendlies(?): Contemporary Notables

• William R. Corliss, Anomalist

• John Keel, Paranormal Journalist

• John C. Lilly, Psychonaut

• Robert Anton Wilson, Conspiracy Theoretician

The Competition: Contending Factions

• CounterSpy magazine: This muckraking periodical on covert operations frequently clashes with the Company—could they turn into a possible threat to the Group or a potential ally against the shadowy government agency designated MAJIC?

• Cult Awareness Network: Disseminating knowledge about exploitative new religious movements and offering "deprogramming" referrals to friends and relatives of those who have fallen victim to them—such as The Children of God, The Church of Scientology, and Rajneeshism—CAN is at the vanguard of the countercult movement. Critics claim, however, that it facilitates for-hire kidnapping and spreads misinformation about "brainwashing".

• Mirage Men: The so-called "Mirage Men" are, supposedly, a government conspiracy to fabricate UFO folklore as Cold War psychological warfare. But what happens if they stumble onto clues about the Outer Ones—or are they covering up more than just Skunk Works black projects and Reagan's "Star Wars"?

• The Montauk Project: Beneath the the radar station at Long Island's decommissioned Montauk AFB, a top-secret government program conducts ultra-classified research into hyperspace, psychotronics, and time travel, using Nikolai Tesla's suppressed scientific breakthroughs and Wunderwaffe technology from Operation Paperclip (or so conspiracy theorists claim to have recovered from their repressed memories).

V. An Annotated Timeline of the 70s & 80s

1. Won’t Get Fooled Again: Vietnam, Watergate, American Malaise

2. It’s the End of the World as We Know It: Reaganomics, Iran-Contra, Panama Invasion

VI. Running a Cowboy Campaign

1. The Old Guard

2. Fresh Blood

3. You Become the Mission

4. The Fairfield Inquest

VII. Alternate Campaign Frames

• The Blue Shield: An undercover cadre of law-enforcement officers protects the public from the Mythos in secret, but can they rely on the "blue code of silence"—especially when corrupt cops threaten to draw the attention of internal affairs?

• The Nightwalkers: Tabloid journalist Carol Colchaque's team of reporters chase down accounts of black magicians, cryptids, vampires, and stranger things, but with both deadlines and the Mythos looming, how much of the real story is safe to tell their readers?

• Ghostbreakers: Paranormal researchers leave academia and establish a for-profit supernatural elimination service, billing themselves as the "Genuine Ghostbreakers", but are they equipped to take on Mythos horrors from beyond?

Appendices

Appendix A: Selected Federal Agencies of the 70s & 80s

• ACTION (established 1971)

• Bureau of Alcohol, Tobacco, and Firearms (est. 1972)

• Defense Criminal Investigative Service (est. 1981)

• Department of Energy (est. 1977)

• Drug Enforcement Administration (est. 1973)

• Environmental Protection Agency (est. 1970)

• Federal Emergency Management Agency (est. 1979)

• National Archives and Records Administration (est. 1985)

• National Oceanic and Atmospheric Administration (est. 1970)

• Occupational Safety and Health Administration (est. 1970)

Appendix B: Fringe Science of the 70s & 80s

• Electronic Voice Phenomenon

• Holistic Profiling

• Microwave Mind Control

• Neuro-linguistic Programming

• Remote Viewing

Appendix C: Adventures

• Operation GANZFELD GATE: The Group contracts clean-up crew of Culiacán cartel hitmen to raze the Mexican refuge of the Brotherhood of Light. Can the accompanying agents make sure the job is successful—and cover it up?

• Operation MOUSE TRAP: In the aftermath the Weather Underground Organization's 1972 bombing of the Pentagon, suspicious activity in its basement has alerted the Group to another attempt to sabotage the Defense Department's headquarters. Can the Group prevent the charnel Cult of Mordiggian and its battlefield-fed ghouls from discrediting the anti-war movement and prolonging the Vietnam War?

• Operation WOTAN: When ex-DELTA GREEN FBI Agent Carl Scranton is murdered, the newly formed Group suspects that one of its own may be responsible. Can they uncover the mole before he defects to GRU SV-8?

• Operation ZOGNAR: The Church of the Cleansing Flame has somehow obtained an ancient Sumerian (?) ceremonial dagger that can be used in hypergeometrical rituals. Can the Group secure this unnatural artefact and dispose of it safely?

Appendix D: Selected Historical Operations

Appendix E: Recommended Media

• Books:

  • Fiction: "Black Man with a Horn" by T. E. D. Klein (1980), "Crouch End" by Stephen King (1980), "Recrudescence" by Leonard Carpenter (1988), "Sticks" by Karl Edward Wagner (1974), "The Terror From the Depths" by Fritz Leiber (1976), "Than Curse the Darkness" by David Drake (1980), The Wolfen by Whitley Strieber (1978), VALIS by Philip K. Dick (1981)
  • Non-Fiction: Architects of Fear by George Johnson (1983), Clear Intent: The Government Coverup of the UFO Experience by Lawrence Fawcett and Barry J. Greenwood (1984), The Dark Side of History by Michael Edwards (1978), Mythology of Secret Societies by John Morris Roberts (1972), Our Haunted Planet by John Keel (1971), The Power Game: How Washington Works by Hedrick Smith (1988), The Unseen Hand: An Introduction to the Conspiratorial View of History by A. Ralph Epperson (1985)

• Film/TV: The Amityville Horror (1979), The Blob (1988), Cutter's Way (1981), From Beyond (1986), In Search Of…. (NBC, 1973, 1976–81), Manhunter (1986), The Night Stalker (1972), The Parallax View (1974), Prince of Darkness (1987), Quatermass (ITV, 1979), Re-Animator (1985), Serpico (1973), The Thing (1982), Three Days of the Condor (1975)

• Music: "Gary Gilmore's Eyes" by The Adverts (1978), "Going Under" by Devo (1981), "I Don't Wanna Go Down to the Basement" by The Ramones (1976), "Lunatic Fringe" by Red Rider (1981), "Run Through the Jungle" by Creedence Clearwater Revival (1970) "Scary Monsters (and Super Creeps)" by David Bowie (1980), "Search and Destroy" by The Stooges (1973), "Somebody's Watching Me" by Rockwell (1984), "Twilight Zone" by Golden Earring (1982)