Useful links
Here are some people I work with regularly who I recommend:
Kate Tilton's Author Services
If you need help getting clarity and moving forward with your author business, talk to Kate. She's hugely experienced in the publishing process, book marketing, and business strategy.
Joanna Penn
If you are a self-published author and you don't already know Joanna's work, you need to check her out. She has multiple books for authors, a podcast, and is always at the forefront of whatever is going on in the self-publishing world. Oh, and she has a couple of Shopify sites too ;)