Disclaimer: The author does not source books; however, he is interested in helping members of the church. Here are suggestions and possible sources that may be beneficial. These organizations are all owned and operated by members of the church of Christ.
For books in print,
Freed-Hardeman University Bible Bookstore
Web Site: http://www.fhu.edu/
For books reprinted,
Web Site: http://www.hesterpublications.com/
For books out of print,