737-358-6750

The Liberty Book Publisher uses 737-358-6750, 737-327-3852, 737-374-8622, 737-350-8900

This number is listed on their website, not the others.
You do not mention if you are receiving unsolicited calls from them, or if you are aware of these numbers because you have been doing business with this company.

They are not one of the major publishing companies and would fall into the category of a "Vanity Press".
No reports of outright scamming, but a customer would still need to evaluate what they charge for their services versus what they deliver.  Historically, "Vanity Presses" tend to charge large amounts for their services and deliver a product that (while meeting the contract terms) ends up being a financial loss for the customer.
The few sites I found (other than their own) that have reviews for them listed nearly straight 5 of 5 reviews.  The reviews on each of those sites were also all posted withing a very short period of time, making it appear that this company may do a bit of unethical "self-promotion".