Most probably a scam
Ordered a couple of books via this website that at first seemed legit. Then after a week I started wondering why I'm not getting a confirmation for my order so I went to see what the status of my order was, and it said "Pending payment". This seemed strange as I had immediately paid for my order via PayPal so I used the email bookhubus.com have to contact them. After one day Mailer-Daemon said they can't reach the recipient. The site claims to have a contact form on their website, but there is only an error message. I got suspicious so I went through a whole lot of scam checks, and about 90 % of scam checking sites give bookhub.us a very low score.
Oh, the street address they have on their site, shows a very sus-looking, poorly residential area in Massachusetts, which probably has even nothing to do with whoever operates bookhubus.com.