In order to qualify for a work permit (as a non EEA citizen), you would need to fall under one of these categories

Employment Permit types
Critical Skills Employment Permit
Dependant/Partner/Spouse Employment Permit
Intra-Company Transfer Employment Permit
General Employment Permit
Contract for Services Employment Permit
Reactivation Employment Permit
Internship Employment Permit
Sport and Cultural Employment Permit
Exchange Agreement Employment Permit

You can find links and details for each here https://enterprise.gov.ie/en/What-We-Do/Workplace-and-Skills/Employment-Permits/

Have you researched these to see if your eligible?

I have spent the past 7 years earning a living through the sale of my books. Though royalty payments have fluctuated I am in a position now where I make a steady income (above Irish minimum wage) and am capable of supporting myself. The vast majority of my royalty payments come from Amazon. 

I have scoured the INIS website trying to figure out what and reached out (via email) to the office but have yet to hear back from anyone. I am sure the Covid19 situation is slowing things down but am a bit stuck when it comes to figuring out which residency permit I would apply for.

An Irish friend suggested I reach out the the embassy but I thought I'd post the question here before I take that route. 

Can anyone direct me either to which employment scheme I would fall under or who to reach out to get that information? Thanks!