If you're new to the ecommerce game and just about to make the plunge, Shopify Newbies is a strong group with close to 100,000 members that can help you get started on your Shopify ecommerce business journey.
A collaboration-focused Slack community of Shopify and Shopify Plus partners. This invite-only community has almost every significant person from the Shopify partners community. If invited, the group charges a $149 quarterly fee.
A Facebook group focused on dropshipping and Shopify store owners hustling from France.
Join the official Slack community for Shopify Partners such as app developers, theme developers, Shopify agencies and other ecosystem partners who work towards enabling merchants. It's a large and active community of people all across the world, and is also the official channel for Shopify Partner Townhalls.
A group created by Harry Coleman for likeminded e-commerce entrepreneurs to network with each other. Join to find tutorials and discussions around finding winning products and scaling your Facebook ads, marketing, and dropshipping efforts.
While not specifically about ecommerce, r/smallbusiness is a great place to ask questions and learn from others who are starting, owning and growing a small business.