When searching for questions about writing (including grammar questions), publishing, marketing and more. These websites & forums offer a great deal of useful information and guidance.
Founder Mark Coker makes it easy to publish your great American novel. He provides a free Style Guide and an eBook on Marketing, and more.
An independent forum for Smashwords authors. Offers advice on a variety of self-publishing topics.
Huge forum with focus on many genres.
Lots of interaction among writers.
Writing Forums -- Beta Readers Group
Small group on Writers Forum focused on writers seeking Beta Readers and writers willing to Beta Read the work of other writers.
Science Fiction and Fantasy World Discussion Forum
Interesting emphasis on successful published authors.
Women Writers and Women's Books
Lots of useful articles.
The Book Designer
An incredible site, full of information about how to format an eBook and more.
Look at the various interviews and articles about forensics.
Purdue Writing Lab
NonFiction Advice Sites
Amazing Stories Magazine
There are many sites that solicit or accept article submissions but often there is no compensation other than to promote you as an author or writer. But, they are useful in building your resume and promoting your work.
Most sites want articles relevant to their audience. Review the site contents. Look for submission requirements before making a submission or query.
As of 5/16/2019, the vendors below are my go-to online eBook and POD Publishers:
The Write Place