A compilation of George R.R. Martin novellas, prequels to A Song of Ice and Fire enters the top 5 this week, along with some a new installment of the Mistborn series and new Mitch Rapp novel. 

#1 Recommendations for readers who enjoyed The Survivor by Vince Flynn and Kyle Mills, conspiracy theories and government coverups:

The Octopus: secret government and the death of Danny Casolaro by Kenn Thomas and Jim Keith

The Manchurian Candidate by Richard Condon

JFK: The CIA, Vietnam and the Plot to Assassinate John F. Kennedy by L. Fletcher Prouty

#2 Recommendations for readers who enjoyed The Martian by Andy Weir, more survival stories:

Annihilation by Jeff Vadermeer

The Strain by Guillermo Del Toro

Lock In by John Scalzi

#3 Recommendations for readers who enjoyed A Knight of the Seven Kingdoms by George R.R. Martin, more fantasy novellas and short stories:

The short second life of Bree Tanner : an Eclipse novella by Stephanie Meyer

Stranger Things Happen by Kelly Link

Trigger Warnings: short fictions and disturbances by Neil Gaiman

#4 Recommendations for readers who enjoyed The Murder House by James Patterson & David Ellis, more creepy houses:

The Haunting of Hill House by Shirley Jackson

The Shining by Stephen King (technically a hotel)

House of Leaves by Mark Z. Danielewski

#5 Recommendations for readers who enjoyed Shadows of Self by Brandon Sanderson, more epic fantasy:

The Earthsea cycle by Ursula K. LeGuin (a classic coming-of-age story about wizards)

Katharine Kerr's Westlands series (A Time of Exile is the first)

Half a King by Joe Abercrombie (a fantastical quest)