Q. Are there commentaries other than the ones in the reference room; ones that can be checked out?
Yes. In fact there are more commentaries in the stacks than there are in the reference room. Some are kept together in sets (Anchor Bible, for example, can be found at BS192.2...), but most will be found at the call number for the book of the Bible that you are researching. Each book of the Bible has its own call number section.