Startup Playbook by Hatch Quarter - A guide to building your startup
PeerBoard - The easiest way to build your community without coding
On Slack by Standuply - The most extensive book on using Slack to the utmost
Indie Hackers - Connect with fellow entrepreneurs, developers, and bootstrappers who are sharing the strategies and revenue numbers behind their companies.
CS183B - Startup Class - Stanford class taught by Sam Altman & guest speakers
WIP.co - Work in progress. We are a community of makers who help each other ship product.