Startup School - How to start a startup, by Y Combinator
BaseTemplates - The easiest way to build your pitchdeck and raise money
Co-founder's Daily Journal - One of the key issues founders are struggling with is co-founder conflict.
Pitch Deck Hunt - Real pitch decks from 100+ of the best startups
Co-founder Question Cards - Questions to ask your co-founder to know each other better.
Slidebean - Presentations that design themselves