Email Marketing: A Beginner's Guide - Master email marketing with these 3 short ebooks from Drip.
HubSpot Free Email Marketing - Powerful drag and drop email marketing in the HubSpot CRM
Elevatr Email Marketing Automation - Fast and easy email marketing software
Quokka (formerly Kryptowire) - The gold standard in SAST, MAST, IAST, and more!
Grade My Email - Helps you get out of the spam folder.
SaaS Email Marketing Handbook - Double Your MRR With Email Marketing