There isn't a specific ranking of book-writing companies in Chicago, and the landscape of book-writing services may change over time. Additionally, the concept of "book-writing companies" can vary, as some companies focus on offering writing and editing services to help authors write their books, while others may focus on publishing, printing, or distribution aspects of the book industry.

However, I can provide you with a list of some reputable writing and publishing companies in Chicago that have been known to offer book-writing and related services:

Greenleaf Book Group:

Based in Austin, Texas, Greenleaf Book Group provides a range of publishing services, including ghostwriting, editing, design, and marketing. They have worked with both established authors and first-time writers.

Chicago Review Press:

While primarily a publisher, Chicago Review Press also offers editorial services for authors looking to develop their manuscripts.

Edit 911:

Edit 911 is an editing service founded by Ivy League PhDs and offers manuscript editing, proofreading, and critique services.

Windy City Publishers:

This Chicago-based company offers a variety of publishing services, including ghostwriting, editing, and book design.

Scribe Writing (formerly Book in a Box):

Though not based in Chicago, Scribe Writing is a notable company that offers a collaborative Professional book writing service in USA, where they help authors write and publish their books.

UrbanEdge Publishing:

Based in Chicago, UrbanEdge Publishing focuses on urban fiction, non-fiction, and poetry and may offer some writing and editing services.

Please note that it's essential to research and vet any company you consider working with to ensure they are reputable, provide quality services, and align with your specific needs and goals as an author. Look for reviews, testimonials, and any published works from authors they have worked with. Additionally, consider reaching out to potential companies to discuss your project and get a sense of their approach and expertise.