GrowthList - A crowd-sourced list of growth hacks
Growth Hacker Marketing - Ryan Holiday's book, re-released and expanded
Q by SubStrata - Q is your email communication genius for B2B sales.
Your Growth Hacks Aren't Working - Free new book by Steli Efti on B2B customer acquisition
Email Marketing: A Beginner's Guide - Master email marketing with these 3 short ebooks from Drip.
GrowthHackList - 100+ curated growth hacks for makers + early stage startups