Toomail - 500+ blocks for creating email newsletter templates
Really Good Emails - A large collection of good product email design.
HTMLEmail.io - Responsive HTML email templates for startups & developers
Email Love - Email design inspiration, templates and discovery
UI Jar - Hand-picked design inspiration for your real life projects
Stripo - Stripo is an all-in-one email design platform. We enable our clients to build emails of any complexity, including interactive AMP emails, really fast and easy.