Growth Hacker Marketing - Ryan Holiday's book, re-released and expanded
GrowthList - A crowd-sourced list of growth hacks
Your Growth Hacks Aren't Working - Free new book by Steli Efti on B2B customer acquisition
GrowthHackList - 100+ curated growth hacks for makers + early stage startups
Spacedoo - Short actionable marketing hacks
Growth Hack World - Together We Rise