I checked this California company with the Better Business Bureau and it said they are not an accreddited BBB ?

organization. The company is Blue Rectangle and is ociated with Pacific Book Exchange, LLC. They owe me money for books they agreed to buy from me. I mailed the books to them 2-3 weeks ago. Has anyone dealt with them before. How do I find out if they are legit if the BBB doesn't have anything on them?