Reddit mentions of Indestructible Hulk Volume 1: Agent of S.H.I.E.L.D. (Marvel Now) (Incredible Hulk)

Here's some good starting points:

• Captain America by Ed Brubaker vol. 1: The Winter Soldier
  
• Thor: God of Thunder by Jason Aaron vol. 1: The God Butcher
  
• Iron Man by Matt Fraction vol. 1: The Five Nightmares
  
• Indestructible Hulk by Mark Waid vol. 1: Agent of SHIELD
  
• Hawkeye by Matt Fraction vol. 1: My Life as a Weapon
  
• Black Widow by Nathan Edmondson vol. 1: The Finely Woven Thread
  
• Ant-Man by Nick Spencer vol. 1: Second Chance Man
  
• Doctor Strange: The Oath
  
• Guardians of the Galaxy by Abnett and Lanning: The Complete Collection, vol. 1
  
• Avengers by Kurt Busiek vol. 1

There are a few decent starting points, but I would start at Planet Hulk. This was a relatively fresh start for the book, so there's nothing you really need to know from the previous run. This is the beginning of Greg Pak's run on the book.

• Prelude to Planet Hulk
  
• Planet Hulk
  
• World War Hulk
  
  After WWH, Jeph Loeb took over with a new Hulk book. Greg Pak continued onto a spin-off, Skaar, Son of Hulk.
  
  
• Hulk by Jeph Loeb, Vol. 1
  
• Skaar, Son of Hulk, Vol. 1
  
• Skaar, Son of Hulk, Vol. 2
  
  After about a year, they brought back Incredible Hulk with #600 and continued Hulk separately.
  
  
• Hulk by Jeph Loeb, Vol. 2
  
• Incredible Hulks: Fall of the Hulks
  
• Incredible Hulks: World War Hulks
  
  From there, Greg Pak continued on with Incredible Hulks (ending his run) and Jeff Parker was on Hulk.
  
  
• Incredible Hulks, Vol. 1 Dark Son
  
• Incredible Hulks, Vol. 2 Chaos War
  
• Incredible Hulks, Vol. 3 Planet Savage
  
• Incredible Hulks, Vol. 4 Heart of the Monster
  
• Hulk: Scorched Earth
  
• Hulk: Planet Red Hulk
  
• Hulk: Fear Itself
  
• Hulk: Hulk of Arabia
  
• Hulk: Haunted
  
• Hulk: Mayan Rule
  
  A fresh start with Jason Aaron's Incredible Hulk.
  
  
• Incredible Hulk, Vol. 1
  
• Incredible Hulk, Vol. 2
  
  Another fresh start with Mark Waid's Indestructible Hulk.
  
  
• Indestructible Hulk, Vol. 1 Agent of SHIELD
  
• Indestructible Hulk, Vol. 2 Gods & Monsters
  
• Indestructible Hulk, Vol. 3 SMASH Time
  
• Indestructible Hulk, Vol. 4 Humanity Bomb
  
  Then another relaunch with Hulk with Waid to start, but Duggan takes over pretty quickly.
  
  
• Hulk, Vol. 1 Banner DOA
  
• Original Sin: Hulk vs Iron Man

Look for trades, specifically Volume #1s, here's a hulk one to give you an idea, don't be afraid to try new shit either.