As a new WordPress plug-in author one of the most difficult task I faced once the product was ready to be delivered was getting some attention from Wordpress users.
The second step was to get some attention from the major blogs and online magazines focused on the WordPress world. After the first emails sent with a review request without any response I start making some searches on Google and go a little bit deeper on this hard task.
These are the most popular blog post on this issue:
How To Promote Your New WordPress Plugin – My Detailed Guide
Tips For Promoting Newly Released WordPress Plugins
Tips for marketing WordPress products
How to promote your new WordPress plugin?
All You Need to Know About How to Promote WordPress Plugins and Themes
I’ve to say that despite the advices provided by all those authors, the lesson I learned experimenting each of the tricks suggested was that when a product is very good it doesn’t need any marketing at all.
Good plugins sell themselves thank to the word of mouth of their early users.
So my only advice is to struggle to make a very good product first and let its users promoting it for you.
To be honest a little effort on digital PR, backlink tricks to improve your plugin website SEO could be useful, like this post too, but you can invest as many resources and times in marketing as you want but at the end of the day what really matter is the quality of your product.
I’d very happy to hear some stories from other plugin’s authors to understand how they approached to this task.
Thank you very much for sharing your experience and good luck!