Startup School - How to start a startup, by Y Combinator
Founder Resources - FounderResources.io is a curated list of 500+ resources, templates & tools that help you on your journey to build a successful business.
YC World - Explore Y Combinator companies by country
Startup Stash - A curated directory of 400 resources & tools for startups
Y Combinator Companies - Interactive list of all 1000+ YC companies
StartupResources.io - Tightly curated lists of the best startup tools