Email Marketing: A Beginner's Guide - Master email marketing with these 3 short ebooks from Drip.
Content Marketing Stack - A curated directory of content marketing resources
HubSpot Free Email Marketing - Powerful drag and drop email marketing in the HubSpot CRM
The Influencer Marketing Stack - Free resources to launch a killer campaign
Google Sheets Email Marketing - Email automation and validations directly from Google Sheets
Marketing Examples - A gallery of real world marketing case studies. Updated every day.